$ASB
ASSOCIATED BANC-CORP Stock $asb

$asb Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000000778921000018 Filed on February 09, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue			$1.235B
YoY Change			15.02%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$20.80M	$16.70M	$48.25M
YoY Change	24.55%	12.84%	2.74%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense			$274.6M
YoY Change			88.85%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$89.50M	$113.8M	$413.3M
YoY Change	-21.35%	26.59%	22.02%
Income Tax	$17.40M	$39.90M	$79.79M
% Of Pretax Income	19.44%	35.06%	19.3%
Net Earnings	$72.10M	$89.00M	$333.6M
YoY Change	-18.99%	78.0%	45.49%
Net Earnings / Revenue			27.01%
Basic Earnings Per Share			$1.92
Diluted Earnings Per Share	$454.9K	$535.2K	$1.89
COMMON SHARES
Basic Shares Outstanding	159.3M shares	165.8M shares	167.3M shares
Diluted Shares Outstanding			169.7M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$588.7M	$876.7M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$435.3M	$363.2M	$363.0M
YoY Change	19.84%	9.75%	9.67%
Goodwill	$1.200B	$1.200B
YoY Change	0.0%	22.95%
Intangibles	$88.30M	$75.84M
YoY Change	16.44%	386.75%
Long-Term Investments	$280.0M	$161.0M	$161.0M
YoY Change	73.91%	9.52%	9.52%
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$32.39B	$33.62B	$33.62B
YoY Change	-3.66%	10.27%	10.27%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$490.0M	$410.0M	$410.0M
YoY Change	19.51%	28.53%	28.53%
Deferred Revenue
YoY Change
Short-Term Debt	$465.1M	$157.1M	$157.0M
YoY Change	196.11%	-59.96%	-59.95%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$490.0M	$410.0M	$410.0M
YoY Change	19.51%	28.53%	28.53%
LONG-TERM LIABILITIES
Long-Term Debt	$549.0M	$796.0M	$796.0M
YoY Change	-31.03%	60.16%	60.16%
Other Long-Term Liabilities	$0.00	$0.00	$0.00
YoY Change		-100.0%	-100.0%
Total Long-Term Liabilities	$549.0M	$796.0M	$796.0M
YoY Change	-31.03%	40.88%	40.88%
TOTAL LIABILITIES
Total Short-Term Liabilities	$490.0M	$410.0M	$410.0M
Total Long-Term Liabilities	$549.0M	$796.0M	$796.0M
Total Liabilities	$28.46B	$29.83B	$29.83B
YoY Change	-4.59%	9.5%	9.5%
SHAREHOLDERS EQUITY
Retained Earnings	$2.381B	$2.181B
YoY Change	9.14%	12.75%
Common Stock	$1.718B	$1.714B
YoY Change	0.22%	27.91%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$400.5M	$246.6M
YoY Change	62.37%	83.01%
Treasury Stock Shares		10.78M shares
Shareholders Equity	$3.922B	$3.781B	$3.781B
YoY Change
Total Liabilities & Shareholders Equity	$32.39B	$33.62B	$33.62B
YoY Change	-3.66%	10.27%	10.27%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	$72.10M	$89.00M	$333.6M
YoY Change	-18.99%	78.0%	45.49%
Depreciation, Depletion And Amortization	$20.80M	$16.70M	$48.25M
YoY Change	24.55%	12.84%	2.74%
Cash From Operating Activities	$104.3M	$193.9M	$496.6M
YoY Change	-46.21%	36.45%	8.33%
INVESTING ACTIVITIES
Capital Expenditures	-$17.10M	-$23.00M	-$65.90M
YoY Change	-25.65%	58.62%	39.03%
Acquisitions			$59.47M
YoY Change			-17643.36%
Other Investing Activities	$52.90M	$25.80M	-$315.0M
YoY Change	105.04%	-113.02%	-76.66%
Cash From Investing Activities	$35.80M	$2.800M	-$380.9M
YoY Change	1178.57%	-101.32%	-72.73%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net			$0.00
YoY Change
Cash From Financing Activities	-310.9M	133.7M	$44.98M
YoY Change	-332.54%	-54.68%	-95.56%
NET CHANGE
Cash From Operating Activities	104.3M	193.9M	$496.6M
Cash From Investing Activities	35.80M	2.800M	-$380.9M
Cash From Financing Activities	-310.9M	133.7M	$44.98M
Net Change In Cash	-170.8M	330.4M	$160.7M
YoY Change	-151.69%	47.24%	117.77%
FREE CASH FLOW
Cash From Operating Activities	$104.3M	$193.9M	$496.6M
Capital Expenditures	-$17.10M	-$23.00M	-$65.90M
Free Cash Flow	$121.4M	$216.9M	$562.5M
YoY Change	-44.03%	38.51%	11.21%

Facts In Submission

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CY2020	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	10200000	USD
CY2019	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	11165000	USD
CY2018	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	9051000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	514056000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	380824000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	355568000	USD
CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	432151000	USD
CY2019	us-gaap	Labor And Related Expense LaborAndRelatedExpense	487063000	USD
CY2018	us-gaap	Labor And Related Expense LaborAndRelatedExpense	482676000	USD
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	81214000	USD
CY2019	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	82429000	USD
CY2018	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	72674000	USD
CY2020	us-gaap	Occupancy Net OccupancyNet	64064000	USD
CY2019	us-gaap	Occupancy Net OccupancyNet	62399000	USD
CY2018	us-gaap	Occupancy Net OccupancyNet	59121000	USD
CY2020	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	18428000	USD
CY2019	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	29600000	USD
CY2018	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	30923000	USD
CY2020	us-gaap	Equipment Expense EquipmentExpense	21705000	USD
CY2019	us-gaap	Equipment Expense EquipmentExpense	23550000	USD
CY2018	us-gaap	Equipment Expense EquipmentExpense	23243000	USD
CY2020	asb	Legal And Professional Fees LegalAndProfessionalFees	21546000	USD
CY2019	asb	Legal And Professional Fees LegalAndProfessionalFees	19901000	USD
CY2018	asb	Legal And Professional Fees LegalAndProfessionalFees	23061000	USD
CY2020	asb	Loan Expense LoanExpense	12600000	USD
CY2019	asb	Loan Expense LoanExpense	8861000	USD
CY2018	asb	Loan Expense LoanExpense	7410000	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	20350000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	16250000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	8159000	USD
CY2020	asb	Loss On Prepayments Of Fhlb Advances LossOnPrepaymentsOfFHLBAdvances	44650000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	46688000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	46666000	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	30000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	10192000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9948000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	55530000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	776034000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	793988000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	821799000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	326972000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	406509000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	413349000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	20200000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79720000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79786000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	306771000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	326790000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	333562000	USD
CY2020	us-gaap	Preferred Stock Dividends And Other Adjustments PreferredStockDividendsAndOtherAdjustments	18358000	USD
CY2019	us-gaap	Preferred Stock Dividends And Other Adjustments PreferredStockDividendsAndOtherAdjustments	15202000	USD
CY2018	us-gaap	Preferred Stock Dividends And Other Adjustments PreferredStockDividendsAndOtherAdjustments	10784000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	288413000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	311587000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	322779000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.87
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.93
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.92
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.86
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.91
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.89
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	153005000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	160534000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	167345000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	153642000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	161932000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	169732000	shares
CY2020	us-gaap	Net Income Loss NetIncomeLoss	306771000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	326790000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	333562000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	55628000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	111592000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-39891000	USD
CY2020	asb	Amortizationof Net Unrealized Gainon Availablefor Sale Securities Transferedto Heldtomaturity Securities AmortizationofNetUnrealizedGainonAvailableforSaleSecuritiesTransferedtoHeldtomaturitySecurities	-3359000	USD
CY2019	asb	Amortizationof Net Unrealized Gainon Availablefor Sale Securities Transferedto Heldtomaturity Securities AmortizationofNetUnrealizedGainonAvailableforSaleSecuritiesTransferedtoHeldtomaturitySecurities	-895000	USD
CY2018	asb	Amortizationof Net Unrealized Gainon Availablefor Sale Securities Transferedto Heldtomaturity Securities AmortizationofNetUnrealizedGainonAvailableforSaleSecuritiesTransferedtoHeldtomaturitySecurities	572000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	9222000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	5957000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-1985000	USD
CY2020	asb	Changein Equity Securities201601 ChangeinEquitySecurities201601	0	USD
CY2019	asb	Changein Equity Securities201601 ChangeinEquitySecurities201601	0	USD
CY2018	asb	Changein Equity Securities201601 ChangeinEquitySecurities201601	84000	USD
CY2020	asb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoci Reclass Tax Effectbefore Tax Total OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIReclassTaxEffectbeforeTaxTotal	0	USD
CY2019	asb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoci Reclass Tax Effectbefore Tax Total OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIReclassTaxEffectbeforeTaxTotal	0	USD
CY2018	asb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoci Reclass Tax Effectbefore Tax Total OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIReclassTaxEffectbeforeTaxTotal	-8419000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	12429000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	26898000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-9791000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	37336000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	79631000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-37189000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-148000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-148000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-148000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	7780000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	16296000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-28612000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Reclassification Adjustments And Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax	3897000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Reclassification Adjustments And Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax	476000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Reclassification Adjustments And Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax	2203000	USD
CY2020	asb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Defined Benefits Tax Effect Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIDefinedBenefitsTaxEffectBeforeTax	0	USD
CY2019	asb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Defined Benefits Tax Effect Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIDefinedBenefitsTaxEffectBeforeTax	0	USD
CY2018	asb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Defined Benefits Tax Effect Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIDefinedBenefitsTaxEffectBeforeTax	5235000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-3064000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-4465000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	6767000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-8465000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-12158000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	25025000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	45801000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	91789000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-62214000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	352572000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	418579000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	271348000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	3237443000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	333562000	USD
CY2018	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-48476000	USD
CY2018	asb	Adoption Of New Accounting Standard Asu201613 AdoptionOfNewAccountingStandardASU201613	-13738000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	271348000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	18408000	USD
CY2018	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	488408000	USD
CY2018	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	-33075000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	105519000	USD
CY2018	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	10784000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	97315000	USD
CY2018	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	537000	USD
CY2018	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	1000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	17107000	USD
CY2018	asb	Tax Act Reclassification TaxActReclassification	13654000	USD
CY2018	asb	Change In Accounting Principal ChangeInAccountingPrincipal	84000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	632000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	3780888000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	326790000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	91789000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	418579000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	11216000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	111804000	USD
CY2019	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	15202000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	24854000	USD
CY2019	us-gaap	Stockholders Equity Other StockholdersEquityOther	-331000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	3922124000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	306771000	USD
CY2020	us-gaap	Mortgage Servicing Rights Msr Impairment Recovery MortgageServicingRightsMSRImpairmentRecovery	17704000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	45801000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	352572000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	96796000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	3966000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	112023000	USD
CY2020	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	18358000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	21561000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	4090933000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	306771000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	326790000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	333562000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	174006000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	16000000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
CY2020	us-gaap	Depreciation Depreciation	50567000	USD
CY2019	us-gaap	Depreciation Depreciation	58149000	USD
CY2018	us-gaap	Depreciation Depreciation	48253000	USD
CY2019	us-gaap	Mortgage Servicing Rights Msr Impairment Recovery MortgageServicingRightsMSRImpairmentRecovery	63000	USD
CY2018	us-gaap	Mortgage Servicing Rights Msr Impairment Recovery MortgageServicingRightsMSRImpairmentRecovery	-545000	USD
CY2020	us-gaap	Amortization Of Mortgage Servicing Rights Ms Rs AmortizationOfMortgageServicingRightsMSRs	22664000	USD
CY2019	us-gaap	Amortization Of Mortgage Servicing Rights Ms Rs AmortizationOfMortgageServicingRightsMSRs	12432000	USD
CY2018	us-gaap	Amortization Of Mortgage Servicing Rights Ms Rs AmortizationOfMortgageServicingRightsMSRs	9594000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	10192000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9948000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	8159000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-25028000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-23573000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-11624000	USD
CY2020	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	25556000	USD
CY2019	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	20062000	USD
CY2018	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	19425000	USD
CY2020	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	9222000	USD
CY2019	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	5957000	USD
CY2018	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	-1985000	USD
CY2020	asb	Gains Losses On Sales Of Ppe And Other Assets GainsLossesOnSalesOfPPEAndOtherAssets	155589000	USD
CY2019	asb	Gains Losses On Sales Of Ppe And Other Assets GainsLossesOnSalesOfPPEAndOtherAssets	2713000	USD
CY2018	asb	Gains Losses On Sales Of Ppe And Other Assets GainsLossesOnSalesOfPPEAndOtherAssets	-1103000	USD
CY2020	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	7449000	USD
CY2019	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2018	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2020	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	59379000	USD
CY2019	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	20120000	USD
CY2018	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	22497000	USD
CY2020	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	1642135000	USD
CY2019	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	1090792000	USD
CY2018	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	1092318000	USD
CY2020	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1959571000	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1317077000	USD
CY2018	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1131652000	USD
CY2020	us-gaap	Pension Contributions PensionContributions	0	USD
CY2019	us-gaap	Pension Contributions PensionContributions	0	USD
CY2018	us-gaap	Pension Contributions PensionContributions	41877000	USD
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-933000	USD
CY2019	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-7595000	USD
CY2018	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	7417000	USD
CY2020	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-11385000	USD
CY2019	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	2495000	USD
CY2018	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	10407000	USD
CY2020	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-29057000	USD
CY2019	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	723000	USD
CY2018	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	30924000	USD
CY2020	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	-113760000	USD
CY2019	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	-102966000	USD
CY2018	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	40950000	USD
CY2020	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-47268000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	43908000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	18178000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-32270000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	42005000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	4594000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	550020000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	574260000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	496567000	USD
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1640524000	USD
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	137990000	USD
CY2018	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	326464000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	1648938000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	460124000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	737580000	USD
CY2020	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	125480000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	423682000	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	682622000	USD
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	84152000	USD
CY2019	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	246836000	USD
CY2018	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	347323000	USD
CY2020	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	54682000	USD
CY2019	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	67459000	USD
CY2018	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	65854000	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	200000	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	0	USD
CY2018	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	0	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	626283000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	1367476000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	601130000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	144000000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	270023000	USD
CY2018	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	282145000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1617446000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1343056000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	561659000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	633859000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	449078000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	260510000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	217836000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Other Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments	27964000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Other Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments	10250000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Other Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments	41856000	USD
CY2020	asb	Net Changein Tax Credit Investments NetChangeinTaxCreditInvestments	55134000	USD
CY2019	asb	Net Changein Tax Credit Investments NetChangeinTaxCreditInvestments	67632000	USD
CY2018	asb	Net Changein Tax Credit Investments NetChangeinTaxCreditInvestments	57327000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	31518000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	551250000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	59472000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-793737000	USD
CY2019	asb	Net Decrease In Deposits Due To Branch Sales NetDecreaseInDepositsDueToBranchSales	0	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-380872000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	2497378000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-1842748000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	270481000	USD
CY2020	asb	Net Decrease In Deposits Due To Branch Sales NetDecreaseInDepositsDueToBranchSales	-222878000	USD
CY2018	asb	Net Decrease In Deposits Due To Branch Sales NetDecreaseInDepositsDueToBranchSales	0	USD
CY2020	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-238655000	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	308039000	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-581371000	USD
CY2020	asb	Proceedsfrom Repaymentofshortterm Fhlb Advances ProceedsfromRepaymentofshorttermFHLBAdvances	-520000000	USD
CY2019	asb	Proceedsfrom Repaymentofshortterm Fhlb Advances ProceedsfromRepaymentofshorttermFHLBAdvances	-380000000	USD
CY2018	asb	Proceedsfrom Repaymentofshortterm Fhlb Advances ProceedsfromRepaymentofshorttermFHLBAdvances	616000000	USD
CY2020	asb	Repaymentof Fhlb Advance RepaymentofFHLBAdvance	-1040972000	USD
CY2019	asb	Repaymentof Fhlb Advance RepaymentofFHLBAdvance	-764657000	USD
CY2018	asb	Repaymentof Fhlb Advance RepaymentofFHLBAdvance	-2150016000	USD
CY2020	asb	Proceedsfrom Fhlb Advance ProceedsfromFHLBAdvance	-4215000	USD
CY2019	asb	Proceedsfrom Fhlb Advance ProceedsfromFHLBAdvance	-751573000	USD
CY2018	asb	Proceedsfrom Fhlb Advance ProceedsfromFHLBAdvance	-1837680000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	250000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1081000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1000	USD
CY2018	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	300000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	96796000	USD
CY2019	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	97315000	USD
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	3966000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	11216000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	18408000	USD
CY2020	us-gaap	Payments For Repurchase Of Warrants PaymentsForRepurchaseOfWarrants	0	USD
CY2019	us-gaap	Payments For Repurchase Of Warrants PaymentsForRepurchaseOfWarrants	0	USD
CY2018	us-gaap	Payments For Repurchase Of Warrants PaymentsForRepurchaseOfWarrants	1000	USD
CY2020	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2019	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2018	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	537000	USD
CY2020	asb	Paymentsforreturnedtoauthorizedbutunissuedcommonstock Paymentsforreturnedtoauthorizedbutunissuedcommonstock	0	USD
CY2019	asb	Paymentsforreturnedtoauthorizedbutunissuedcommonstock Paymentsforreturnedtoauthorizedbutunissuedcommonstock	0	USD
CY2018	asb	Paymentsforreturnedtoauthorizedbutunissuedcommonstock Paymentsforreturnedtoauthorizedbutunissuedcommonstock	33075000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	112023000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	111804000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	105519000	USD
CY2020	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	18358000	USD
CY2019	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	15202000	USD
CY2018	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	10784000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	371020000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2479660000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	44983000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	127304000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-287954000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	160678000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	588744000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	876698000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	716018000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	716048000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	588744000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	876698000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	159291000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	332919000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	261724000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	17734000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	41131000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	18335000	USD
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	19261000	USD
CY2019	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	10513000	USD
CY2018	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	26517000	USD
CY2020	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	13667000	USD
CY2019	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	11606000	USD
CY2018	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	10722000	USD
CY2020	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	264570000	USD
CY2019	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	313570000	USD
CY2018	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	33010000	USD
CY2020	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	0	USD
CY2019	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	692414000	USD
CY2018	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	0	USD
CY2020	asb	Unsettled Trades To Purchase Securities UnsettledTradesToPurchaseSecurities	0	USD
CY2019	asb	Unsettled Trades To Purchase Securities UnsettledTradesToPurchaseSecurities	0	USD
CY2018	asb	Unsettled Trades To Purchase Securities UnsettledTradesToPurchaseSecurities	883000	USD
CY2020Q4	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets	456480000	USD
CY2019Q4	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets	695848000	USD
CY2018Q4	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets	2567488000	USD
CY2020Q4	asb	Business Combination Recognized Identifiable Assets Acquiredand Liabilities Assumed Intangible Assets Including Goodwill BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedIntangibleAssetsIncludingGoodwill	23548000	USD
CY2019Q4	asb	Business Combination Recognized Identifiable Assets Acquiredand Liabilities Assumed Intangible Assets Including Goodwill BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedIntangibleAssetsIncludingGoodwill	29837000	USD
CY2018Q4	asb	Business Combination Recognized Identifiable Assets Acquiredand Liabilities Assumed Intangible Assets Including Goodwill BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedIntangibleAssetsIncludingGoodwill	261243000	USD
CY2020Q4	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	480028000	USD
CY2019Q4	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	725764000	USD
CY2018Q4	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	2340323000	USD
CY2020Q4	asb	Equity Issued In Adjustments Related To Acquisition EquityIssuedInAdjustmentsRelatedToAcquisition	0	USD
CY2019Q4	asb	Equity Issued In Adjustments Related To Acquisition EquityIssuedInAdjustmentsRelatedToAcquisition	79000	USD
CY2018Q4	asb	Equity Issued In Adjustments Related To Acquisition EquityIssuedInAdjustmentsRelatedToAcquisition	488408000	USD
CY2020Q4	us-gaap	Cash Equivalents At Carrying Value CashEquivalentsAtCarryingValue	716048000	USD
CY2019Q4	us-gaap	Cash Equivalents At Carrying Value CashEquivalentsAtCarryingValue	400232000	USD
CY2018Q4	us-gaap	Cash Equivalents At Carrying Value CashEquivalentsAtCarryingValue	782784000	USD
CY2020Q4	us-gaap	Restricted Cash RestrictedCash	0	USD
CY2019Q4	us-gaap	Restricted Cash RestrictedCash	188512000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	588744000	USD
CY2018Q4	us-gaap	Restricted Cash RestrictedCash	93914000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	716048000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	876698000	USD
CY2020Q1	us-gaap	Financing Receivable Purchased With Credit Deterioration Amount At Par Value FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue	79774000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	201371000	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	21907000	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	61000	USD
CY2020Q1	us-gaap	Financing Receivable Purchased With Credit Deterioration Amount At Purchase Price FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice	77221000	USD
CY2020Q1	us-gaap	Financing Receivable Purchased With Credit Deterioration Allowance For Credit Loss At Acquisition Date FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate	3504000	USD
CY2020Q1	us-gaap	Financing Receivable Purchased With Credit Deterioration Discount Premium FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium	-951000	USD
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	3028399000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	60612000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	3570000	USD
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	3085441000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	1879005000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	149938000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	2028943000	USD
CY2019Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	3251950000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	30920000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	20284000	USD
CY2019Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	3262586000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	2205083000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	79744000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	8363000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	2276465000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	7385000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	7394000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	29665000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	29938000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	83293000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	84112000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	54313000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	56196000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	350687000	USD
CY2020Q4	asb	Ratio Of Fair Value To Amortized Cost Htm RatioOfFairValueToAmortizedCostHtm	1.080
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	371076000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	187853000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	197850000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	38113000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	42650000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	1171068000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	1292485000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	479478000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	505231000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	1442900000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	1576469000	USD
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	3028399000	USD
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	3085441000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	1879005000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	2028943000	USD
CY2020Q4	asb	Ratioof Fair Valueto Amortized Cost Afs RatioofFairValuetoAmortizedCostAFS	1.019
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	1879005000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	9312000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	6374000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1954000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	90000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	13861000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	3938000	USD
CY2020	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	USD
CY2019	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	13444000	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	USD
CY2020	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	9222000	USD
CY2019	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	5957000	USD
CY2018	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	-1985000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	626283000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	1367476000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	601130000	USD
CY2020Q2	asb	Debt Securities Afs Principal Sold DebtSecuritiesAFSPrincipalSold	261000000	USD
CY2020Q2	us-gaap	Gain Loss On Sales Of Mortgage Backed Securities Mbs GainLossOnSalesOfMortgageBackedSecuritiesMBS	3000000	USD
CY2020Q1	asb	Debt Securities Afs Principal Sold DebtSecuritiesAFSPrincipalSold	281000000	USD
CY2020Q1	us-gaap	Gain Loss On Sales Of Mortgage Backed Securities Mbs GainLossOnSalesOfMortgageBackedSecuritiesMBS	6000000	USD
CY2019	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	692000000	USD
CY2019	asb	Debt Securities Afs Principal Sold DebtSecuritiesAFSPrincipalSold	157000000	USD
CY2019	us-gaap	Debt Securities Available For Sale Gain Loss DebtSecuritiesAvailableForSaleGainLoss	3000000	USD
CY2019	asb	Carrying Amount Of Securities Sold Credit CarryingAmountOfSecuritiesSoldCredit	1200000000	USD
CY2019	asb	Visa B Restricted Stock Donated VisaBRestrictedStockDonated	42039	shares
CY2019	asb	Visa Restricted Stock Owned At Fair Value VisaRestrictedStockOwnedAtFairValue	77000	shares
CY2018	us-gaap	Availableforsale Securities Sold At Par AvailableforsaleSecuritiesSoldAtPar	108000000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	2600000000	USD
CY2020Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	1600000000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Past Due DebtSecuritiesHeldToMaturityPastDue	0	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	-67000	USD
CY2020Q4	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	27	security
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	685000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	192720000	USD
CY2020Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	16	security
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	2885000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	178681000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	3570000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	371400000	USD
CY2020Q4	asb	Heldtomaturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positionslessthan12 Months HeldtomaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionslessthan12Months	1	security
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	325000	USD
CY2020Q4	asb	Heldtomaturity Securitiesin Unrealized Loss Positions Qualitative Disclosure Numberof Positions12 Monthsor Longer HeldtomaturitySecuritiesinUnrealizedLossPositionsQualitativeDisclosureNumberofPositions12MonthsorLonger	0	security
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	325000	USD
CY2019Q4	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	65	security
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	7843000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	834616000	USD
CY2019Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	51	security
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	12440000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	748487000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	20284000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	1583104000	USD
CY2019Q4	asb	Heldtomaturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positionslessthan12 Months HeldtomaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionslessthan12Months	67	security
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	2199000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	292267000	USD
CY2019Q4	asb	Heldtomaturity Securitiesin Unrealized Loss Positions Qualitative Disclosure Numberof Positions12 Monthsor Longer HeldtomaturitySecuritiesinUnrealizedLossPositionsQualitativeDisclosureNumberofPositions12MonthsorLonger	36	security
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	6164000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	367532000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	8363000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	659799000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	82000000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	149000000	USD
CY2020Q4	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	87000000	USD
CY2019Q4	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	78000000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2000000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2000000	USD
CY2020	asb	Visa Restricted Stock Owned Total VisaRestrictedStockOwnedTotal	77996	shares
CY2019	asb	Visa Restricted Stock Owned At Fair Value VisaRestrictedStockOwnedAtFairValue	77000	shares
CY2019	asb	Visa B Restricted Stock Donated VisaBRestrictedStockDonated	42039	shares
CY2020Q1	asb	Visa Restricted Stock Owned At Zero Cost VisaRestrictedStockOwnedAtZeroCost	996	shares
CY2019Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	13000000	USD
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	13000000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	24451724000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	22821440000	USD
CY2020	asb	Financing Receivable Nonaccrual Interest Income String FinancingReceivableNonaccrualInterestIncomeString	3 million
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	16772000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	17831000	USD
CY2020	us-gaap	Loans And Leases Receivable Related Parties Additions LoansAndLeasesReceivableRelatedPartiesAdditions	19140000	USD
CY2019	us-gaap	Loans And Leases Receivable Related Parties Additions LoansAndLeasesReceivableRelatedPartiesAdditions	3673000	USD
CY2020	us-gaap	Loans And Leases Receivable Related Parties Proceeds LoansAndLeasesReceivableRelatedPartiesProceeds	6643000	USD
CY2019	us-gaap	Loans And Leases Receivable Related Parties Proceeds LoansAndLeasesReceivableRelatedPartiesProceeds	8053000	USD
CY2020	asb	Change Due To Status Of Officers And Directors ChangeDueToStatusOfOfficersAndDirectors	-152000	USD
CY2019	asb	Change Due To Status Of Officers And Directors ChangeDueToStatusOfOfficersAndDirectors	-3320000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	29420000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	16772000	USD
CY2020Q4	us-gaap	Financing Receivable Revolving Converted To Term Loan FinancingReceivableRevolvingConvertedToTermLoan	69246000	USD
CY2020Q4	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	3173996000	USD
CY2020Q4	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	6590550000	USD
CY2020Q4	us-gaap	Financing Receivable Originated In Fiscal Year Before Latest Fiscal Year FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear	5127451000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	3189745000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	1937912000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	1770647000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	2661424000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	24451724000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	22821440000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	24202209000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	210854000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	24451724000	USD
CY2020	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2020Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	140000000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	22679696000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	118380000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	22821440000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	110043000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	148020000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	16165000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	113697000	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	3628000	USD
CY2019Q4	asb	Net Recorded Investmentofthe Impaired Loans NetRecordedInvestmentoftheImpairedLoans	0.63
CY2020Q4	asb	Performing Restructured Loans PerformingRestructuredLoans	52092000	USD
CY2020Q4	asb	Nonaccrual Restructured Loans NonaccrualRestructuredLoans	20190000	USD
CY2019Q4	asb	Performing Restructured Loans PerformingRestructuredLoans	26041000	USD
CY2019Q4	asb	Nonaccrual Restructured Loans NonaccrualRestructuredLoans	22494000	USD
CY2018Q4	asb	Performing Restructured Loans PerformingRestructuredLoans	53263000	USD
CY2018Q4	asb	Nonaccrual Restructured Loans NonaccrualRestructuredLoans	26292000	USD
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	36000000	USD
CY2020Q4	asb	Restructured Loans Subsequently Accruing RestructuredLoansSubsequentlyAccruing	30000000	USD
CY2020Q4	asb	Ytd Restructured Loans Still On Nonaccrual YtdRestructuredLoansStillOnNonaccrual	6000000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	11000000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	77	loan
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	36154000	USD
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	37125000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	85	loan
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	15940000	USD
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	16150000	USD
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	86	loan
CY2018	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	11429000	USD
CY2018	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	11792000	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	9	loan
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	1244000	USD
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	66	loan
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	6959000	USD
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	55	loan
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	5241000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	238023000	USD
CY2019	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	19161000	USD
CY2019	asb	Financing Receivable Allowance For Credit Loss Net Recovery Loss FinancingReceivableAllowanceForCreditLossNetRecoveryLoss	-55152000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	18500000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	201371000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Goodwill Goodwill	1100000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1200000000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	67607000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	68433000	USD
CY2017Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	59168000	USD
CY2020	asb	Msr Additionfrom Business Combination MSRAdditionfromBusinessCombination	1357000	USD
CY2019	asb	Msr Additionfrom Business Combination MSRAdditionfromBusinessCombination	0	USD
CY2018	asb	Msr Additionfrom Business Combination MSRAdditionfromBusinessCombination	8136000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	13667000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	11606000	USD
CY2018	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	10722000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	22664000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	12432000	USD
CY2018	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	9594000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	59967000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	67607000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	68433000	USD
CY2019Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	302000	USD
CY2018Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	239000	USD
CY2017Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	784000	USD
CY2020	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisionsRecoveries	17704000	USD
CY2019	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisionsRecoveries	63000	USD
CY2018	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisionsRecoveries	-545000	USD
CY2020Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	18006000	USD
CY2019Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	302000	USD
CY2018Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	239000	USD
CY2020Q4	asb	Servicing Asset At Amortized Value Net ServicingAssetAtAmortizedValueNet	41961000	USD
CY2019Q4	asb	Servicing Asset At Amortized Value Net ServicingAssetAtAmortizedValueNet	67306000	USD
CY2018Q4	asb	Servicing Asset At Amortized Value Net ServicingAssetAtAmortizedValueNet	68193000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value Fair Value ServicingAssetAtAmortizedValueFairValue	41990000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value Fair Value ServicingAssetAtAmortizedValueFairValue	72532000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value Fair Value ServicingAssetAtAmortizedValueFairValue	81012000	USD
CY2020Q4	asb	Portfolio Of Residential Mortgage Loans Serviced For Others PortfolioOfResidentialMortgageLoansServicedForOthers	7743956000	USD
CY2019Q4	asb	Portfolio Of Residential Mortgage Loans Serviced For Others PortfolioOfResidentialMortgageLoansServicedForOthers	8488969000	USD
CY2018Q4	asb	Portfolio Of Residential Mortgage Loans Serviced For Others PortfolioOfResidentialMortgageLoansServicedForOthers	8600983000	USD
CY2020Q4	asb	Mortgage Servicing Rights Net To Servicing Portfolio MortgageServicingRightsNetToServicingPortfolio	0.0054
CY2019Q4	asb	Mortgage Servicing Rights Net To Servicing Portfolio MortgageServicingRightsNetToServicingPortfolio	0.0079
CY2018Q4	asb	Mortgage Servicing Rights Net To Servicing Portfolio MortgageServicingRightsNetToServicingPortfolio	0.0079
CY2020Q4	asb	Mortgage Servicing Rights Expense MortgageServicingRightsExpense	40369000	USD
CY2019Q4	asb	Mortgage Servicing Rights Expense MortgageServicingRightsExpense	12494000	USD
CY2018Q4	asb	Mortgage Servicing Rights Expense MortgageServicingRightsExpense	9049000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	786761000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	367847000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	418914000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	435284000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	11450000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	11006000	USD
CY2020	asb	Finance Lease Cost FinanceLeaseCost	154000	USD
CY2019	asb	Finance Lease Cost FinanceLeaseCost	36000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	11276000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	11305000	USD
CY2020	asb	Finance Lease Payments FinanceLeasePayments	122000	USD
CY2019	asb	Finance Lease Payments FinanceLeasePayments	35000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	31994000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	45381000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	962000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	2188000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	36425000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	49292000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	1128000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2209000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	40806000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y5M12D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0327
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	55580000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y9M29D
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0332
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	1145000	USD
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P1Y7M24D
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0105
CY2019Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	4827000	USD
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P39Y8M1D
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0399
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Rolling Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextRollingTwelveMonths	9120000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	172000	USD
CY2020Q4	asb	Lease Liability Payments Due In Next Twelve Months LeaseLiabilityPaymentsDueInNextTwelveMonths	9293000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	6791000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	973000	USD
CY2020Q4	asb	Lease Liability Payments Due Year Two LeaseLiabilityPaymentsDueYearTwo	7763000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5525000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	0	USD
CY2020Q4	asb	Lease Liability Payments Due Year Three LeaseLiabilityPaymentsDueYearThree	5525000	USD
CY2020Q4	asb	Lessee Operating Lease Lease Notyet Commenced Liability LesseeOperatingLeaseLeaseNotyetCommencedLiability	17000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4760000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	0	USD
CY2020Q4	asb	Lease Liability Payments Due Year Four LeaseLiabilityPaymentsDueYearFour	4760000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3818000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	0	USD
CY2020Q4	asb	Lease Liability Payments Due Year Five LeaseLiabilityPaymentsDueYearFive	3818000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	10792000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	0	USD
CY2020Q4	asb	Lease Liability Payments Due After Year Five LeaseLiabilityPaymentsDueAfterYearFive	10792000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	40806000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	1145000	USD
CY2020Q4	asb	Lease Liability Payments Due Total LeaseLiabilityPaymentsDueTotal	41952000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	4382000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	17000	USD
CY2020Q4	asb	Lease Liability Undiscounted Excess Amount LeaseLiabilityUndiscountedExcessAmount	4399000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	36425000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	1128000	USD
CY2020Q4	asb	Lease Liability LeaseLiability	37553000	USD
CY2019Q4	asb	Lessee Operating Lease Lease Notyet Commenced Liability LesseeOperatingLeaseLeaseNotyetCommencedLiability	16000000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	9208000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable Current OperatingLeasesFutureMinimumPaymentsReceivableCurrent	3148000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	10189000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Two Years OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears	2595000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	6086000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Three Years OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears	1986000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	5439000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Four Years OperatingLeasesFutureMinimumPaymentsReceivableInFourYears	1736000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	4268000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Five Years OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears	1625000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	11679000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable Thereafter OperatingLeasesFutureMinimumPaymentsReceivableThereafter	7568000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	46868000	USD
CY2019	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	5000000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	10000000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable OperatingLeasesFutureMinimumPaymentsReceivable	18658000	USD
CY2020	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	5000000	USD
CY2020	asb	Deposits By Type Tabletext Block DepositsByTypeTabletextBlock	<div style="margin-bottom:5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The distribution of deposits at December 31 is as follows:</span></div><div style="margin-bottom:6pt"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:73.498%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.600%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.602%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">($ in Thousands)</span></td><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td></tr><tr><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Noninterest-bearing demand</span></td><td style="background-color:#dddddd;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">7,661,728 </span></td><td style="background-color:#dddddd;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,450,709 </span></td><td style="background-color:#dddddd;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Savings </span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3,650,085 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">2,735,036 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Interest-bearing demand </span></td><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">6,090,869 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,329,717 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Money market</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">7,322,769 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">7,640,798 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Brokered CDs</span></td><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,964 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Other time</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1,757,030 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">2,616,839 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total deposits</span></td><td style="background-color:#dddddd;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">26,482,481 </span></td><td style="background-color:#dddddd;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">23,779,064 </span></td><td style="background-color:#dddddd;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div>
CY2020Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	7661728000	USD
CY2019Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	5450709000	USD
CY2020Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	3650085000	USD
CY2019Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	2735036000	USD
CY2020Q4	us-gaap	Deposits Negotiable Order Of Withdrawal Now DepositsNegotiableOrderOfWithdrawalNOW	6090869000	USD
CY2019Q4	us-gaap	Deposits Negotiable Order Of Withdrawal Now DepositsNegotiableOrderOfWithdrawalNOW	5329717000	USD
CY2020Q4	us-gaap	Deposits Money Market Deposits DepositsMoneyMarketDeposits	7322769000	USD
CY2019Q4	us-gaap	Deposits Money Market Deposits DepositsMoneyMarketDeposits	7640798000	USD
CY2020Q4	asb	Brokered Certificates Of Deposit BrokeredCertificatesOfDeposit	0	USD
CY2019Q4	asb	Brokered Certificates Of Deposit BrokeredCertificatesOfDeposit	5964000	USD
CY2020Q4	asb	Other Time Deposits OtherTimeDeposits	1757030000	USD
CY2019Q4	asb	Other Time Deposits OtherTimeDeposits	2616839000	USD
CY2020Q4	us-gaap	Deposits Deposits	26482481000	USD
CY2019Q4	us-gaap	Deposits Deposits	23779064000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	682000000	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	1300000000	USD
CY2020Q4	asb	Time Deposits250000 Or More TimeDeposits250000OrMore	341000000	USD
CY2019Q4	asb	Time Deposits250000 Or More TimeDeposits250000OrMore	861000000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	1371671000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	236667000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	77545000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	45185000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	25951000	USD
CY2020Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	11000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	1757030000	USD
CY2020Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	7070000	USD
CY2019Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	362000000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	185901000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	71097000	USD
CY2020Q4	us-gaap	Federal Funds Purchased And Securities Sold Under Agreements To Repurchase FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase	192971000	USD
CY2019Q4	us-gaap	Federal Funds Purchased And Securities Sold Under Agreements To Repurchase FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase	433097000	USD
CY2020Q4	us-gaap	Commercial Paper CommercialPaper	59346000	USD
CY2019Q4	us-gaap	Commercial Paper CommercialPaper	32016000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	252317000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	465113000	USD
CY2020Q4	us-gaap	Subordinated Debt SubordinatedDebt	250000000	USD
CY2019Q4	us-gaap	Subordinated Debt SubordinatedDebt	250000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	1128000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2209000	USD
CY2020Q4	asb	Other Longterm Debtand Capitalized Costs OtherLongtermDebtandCapitalizedCosts	1663000	USD
CY2019Q4	asb	Other Longterm Debtand Capitalized Costs OtherLongtermDebtandCapitalizedCosts	2866000	USD
CY2020Q4	us-gaap	Other Long Term Debt OtherLongTermDebt	549465000	USD
CY2019Q4	us-gaap	Other Long Term Debt OtherLongTermDebt	549343000	USD
CY2020Q4	asb	Total Short Term Long Term Excluding Fhlb TotalShortTermLongTermExcludingFHLB	801782000	USD
CY2019Q4	asb	Total Short Term Long Term Excluding Fhlb TotalShortTermLongTermExcludingFHLB	1014456000	USD
CY2020Q4	asb	Short Term Fhlb Advances ShortTermFHLBAdvances	0	USD
CY2019Q4	asb	Short Term Fhlb Advances ShortTermFHLBAdvances	520000000	USD
CY2020Q4	asb	Long Term Fhlb Advances LongTermFHLBAdvances	1632723000	USD
CY2019Q4	asb	Long Term Fhlb Advances LongTermFHLBAdvances	2660967000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	1632723000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	3180967000	USD
CY2020Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2434505000	USD
CY2019Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	4195422000	USD
CY2020Q4	us-gaap	Carrying Value Of Securities Purchased Under Agreements To Resell And Deposits Paid For Securities Borrowed CarryingValueOfSecuritiesPurchasedUnderAgreementsToResellAndDepositsPaidForSecuritiesBorrowed	262000000	USD
CY2020	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<div style="margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The remaining contractual maturity of the securities sold under agreements to repurchase on the consolidated balance sheets as of December 31, 2020 and December 31, 2019 are presented in the following table:</span></div><div style="margin-bottom:6pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.707%"><tr><td style="width:1.0%"/><td style="width:30.718%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.536%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.536%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.536%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.536%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.538%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="15" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Remaining Contractual Maturity of the Agreements</span></td></tr><tr><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">($ in Thousands)</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Overnight and Continuous</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Up to 30 days</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">30-90 days</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Greater than 90 days</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Total</span></td></tr><tr><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">December 31, 2020</span></td><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Repurchase agreements</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt;text-align:left;vertical-align:top"><div style="padding-left:9pt;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> Agency mortgage-related securities</span></div></td><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">185,901 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">185,901 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">185,901 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">185,901 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">December 31, 2019</span></td><td colspan="3" style="background-color:#dddddd;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:3pt double #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Repurchase agreements</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt;text-align:left;vertical-align:top"><div style="padding-left:9pt;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> Agency mortgage-related securities</span></div></td><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">71,097 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#dddddd;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">71,097 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">71,097 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">71,097 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div>
CY2020Q4	us-gaap	Financial Assets Sold Under Agreements To Repurchase Gross Including Not Subject To Master Netting Arrangement FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement	185901000	USD
CY2019Q4	us-gaap	Financial Assets Sold Under Agreements To Repurchase Gross Including Not Subject To Master Netting Arrangement FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement	71097000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	1600000000	USD
CY2020Q4	asb	Increase Decrease In Fhlb Advances IncreaseDecreaseInFHLBAdvances	-1500000000	USD
CY2020Q4	asb	Decrease In Fhlb Advances Percent DecreaseInFHLBAdvancesPercent	0.49
CY2020Q3	asb	Prepayment Of Fhlb Advances PrepaymentOfFHLBAdvances	950000000	USD
CY2020	asb	Increase Decrease In Short Term Fhlb Advances IncreaseDecreaseInShortTermFHLBAdvances	520000000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	549465000	USD
CY2020Q4	asb	Long Term Funding Weighted Average Coupon Rate LongTermFundingWeightedAverageCouponRate	0.0383
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	1632723000	USD
CY2020Q4	asb	Fhlb Weighted Average Coupon Rate FHLBWeightedAverageCouponRate	0.0234
CY2020Q4	asb	Subsidiary Equity Balance SubsidiaryEquityBalance	4000000000.0	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0350
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0330
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0250
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0160
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0260
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0260
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.2100
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.2400
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.2200
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y9M
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y9M
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y9M
CY2020	asb	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Per Share Fair Value Of Stock Options ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsPerShareFairValueOfStockOptions	2.39
CY2019	asb	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Per Share Fair Value Of Stock Options ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsPerShareFairValueOfStockOptions	4.00
CY2018	asb	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Per Share Fair Value Of Stock Options ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsPerShareFairValueOfStockOptions	4.47
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	5543000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	20.13
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y3M
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	16043000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	1697000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	18.43
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	182000	shares
CY2020	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Accumulated Postretirement Benefit Obligation DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation	141000	USD
CY2020	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Accumulated Postretirement Benefit Obligation1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1	124000	USD
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	13.77
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	585000	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	21.07
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	6473000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	19.77
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y2M23D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	2005000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	4038000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	19.25
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P4Y10M20D
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	1913000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	816000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	4000000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	10000000	USD
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	4000000	USD
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	3000000	USD
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	4000000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	2393000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	22.39
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	1053000	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	18.09
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	936000	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	22.59
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	218000	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	20.86
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	2293000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	20.46
CY2020	asb	Fairvalueofplanassetsasapercentageofnetbenefitobligation Fairvalueofplanassetsasapercentageofnetbenefitobligation	1.71
CY2019	asb	Fairvalueofplanassetsasapercentageofnetbenefitobligation Fairvalueofplanassetsasapercentageofnetbenefitobligation	1.70
CY2020	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Service And Interest Cost Components DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents	5000	USD
CY2020	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Service And Interest Cost Components1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1	4000	USD
CY2019	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Service And Interest Cost Components DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents	7000	USD
CY2019	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Service And Interest Cost Components1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1	6000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	14094000	USD
CY2019	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Accumulated Postretirement Benefit Obligation DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation	170000	USD
CY2019	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Accumulated Postretirement Benefit Obligation1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1	148000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	33020000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	50560000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	20246000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	16193000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	15327000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	12593000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	49213000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	65887000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	32839000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-25895000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	34941000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-3118000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	13833000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	46947000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-261000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	12006000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-29013000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	20200000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79720000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79786000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	88967000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	48790000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	16347000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	7236000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	4673000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	4005000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	27896000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	28018000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other Loss Carryforwards DeferredTaxAssetsOtherLossCarryforwards	9789000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other Loss Carryforwards DeferredTaxAssetsOtherLossCarryforwards	13444000	USD
CY2020Q4	asb	Nonaccrual Interest NonaccrualInterest	1763000	USD
CY2019Q4	asb	Nonaccrual Interest NonaccrualInterest	1299000	USD
CY2020Q4	asb	Basis Difference From Equity Securities And Other Investments BasisDifferenceFromEquitySecuritiesAndOtherInvestments	6329000	USD
CY2019Q4	asb	Basis Difference From Equity Securities And Other Investments BasisDifferenceFromEquitySecuritiesAndOtherInvestments	0	USD
CY2020Q4	asb	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Plan Amendments Tax Effect Unrealized OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansPlanAmendmentsTaxEffectUnrealized	9110000	USD
CY2019Q4	asb	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Plan Amendments Tax Effect Unrealized OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansPlanAmendmentsTaxEffectUnrealized	12174000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	997000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	970000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	165871000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	115936000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	165620000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	115685000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	63113000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	62227000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	21698000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	21099000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	10403000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	17418000	USD
CY2020Q4	asb	Deferred Loan Fee Income DeferredLoanFeeIncome	9799000	USD
CY2019Q4	asb	Deferred Loan Fee Income DeferredLoanFeeIncome	12190000	USD
CY2020Q4	asb	State Income Taxes StateIncomeTaxes	2636000	USD
CY2019Q4	asb	State Income Taxes StateIncomeTaxes	722000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	116000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	199000	USD
CY2020Q4	asb	Deferredtaxliabilitydepreciation Deferredtaxliabilitydepreciation	17757000	USD
CY2019Q4	asb	Deferredtaxliabilitydepreciation Deferredtaxliabilitydepreciation	18348000	USD
CY2020Q4	asb	Purchaseaccounting Purchaseaccounting	12658000	USD
CY2019Q4	asb	Purchaseaccounting Purchaseaccounting	13738000	USD
CY2020Q4	asb	Deferred Tax Liability Basis Difference From Equity Securities And Other Investments DeferredTaxLiabilityBasisDifferenceFromEquitySecuritiesAndOtherInvestments	0	USD
CY2019Q4	asb	Deferred Tax Liability Basis Difference From Equity Securities And Other Investments DeferredTaxLiabilityBasisDifferenceFromEquitySecuritiesAndOtherInvestments	2285000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	13568000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	1139000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	1049000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	1156000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	152797000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	150521000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	12823000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	34836000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	0	USD
CY2019	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	251000	USD
CY2020	asb	Tax Credit Carryforward Expiration Being Date TaxCreditCarryforwardExpirationBeingDate	begin expiring in 2035
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.039
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.033
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.026
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.037
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.035
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.037
CY2020	asb	Bank Owned Life Insurance1 BankOwnedLifeInsurance1	0.009
CY2019	asb	Bank Owned Life Insurance1 BankOwnedLifeInsurance1	0.008
CY2018	asb	Bank Owned Life Insurance1 BankOwnedLifeInsurance1	0.007
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.018
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.009
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.007
CY2020	asb	Increase Decreasein Tax Reserve Adjustments IncreaseDecreaseinTaxReserveAdjustments	0.001
CY2019	asb	Increase Decreasein Tax Reserve Adjustments IncreaseDecreaseinTaxReserveAdjustments	0.002
CY2018	asb	Increase Decreasein Tax Reserve Adjustments IncreaseDecreaseinTaxReserveAdjustments	0.015
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	0.003
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.002
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.005
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.036
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	-0.137
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2020	asb	Fdi Cpremium FDICpremium	0.008
CY2019	asb	Fdi Cpremium FDICpremium	0.005
CY2018	asb	Fdi Cpremium FDICpremium	0.009
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.006
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.003
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.062
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.196
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.193
CY2020Q4	asb	Bad Debt Reserve Of Qualified Thrift Lender BadDebtReserveOfQualifiedThriftLender	100000000	USD
CY2020Q4	asb	Loans Sold To Outside Investors Remaining Outstanding Amount LoansSoldToOutsideInvestorsRemainingOutstandingAmount	6800000000	USD
CY2020Q4	asb	Mortgage Repurchase Reserve MortgageRepurchaseReserve	2000000	USD
CY2020Q4	asb	No Deferred Tax Liability For Aquired Allowance For Bad Debt From Savings Banks NoDeferredTaxLiabilityForAquiredAllowanceForBadDebtFromSavingsBanks	25000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2000000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	3000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	2000000	USD
CY2020Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	72000000	USD
CY2019Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	57000000	USD
CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	31000000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	14000000	USD
CY2020	asb	Asbc Balancesheetoffsettingofderivativeassetsandliabilitiestabletextblock Asbc_balancesheetoffsettingofderivativeassetsandliabilitiestabletextblock	The interest, commodity and foreign exchange agreements the Corporation has with its commercial customers are not subject to an enforceable master netting arrangement, and therefore, are excluded from this table:<table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:15.128%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:16.151%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.326%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:14.835%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.935%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:9.864%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:8.411%"/><td style="width:0.1%"/></tr><tr style="height:29pt"><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" rowspan="2" style="background-color:#00a94f;padding:0 1pt"/><td colspan="12" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross Amounts Subject to Master Netting Arrangements Offset on the Consolidated Balance Sheets</span></td><td colspan="3" rowspan="2" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Net Amounts Presented on the Consolidated Balance Sheets</span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" rowspan="2" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross Amounts Not Offset on the Consolidated Balance Sheets</span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/></tr><tr style="height:21pt"><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">($ in Thousands)</span></div></td><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross Amounts Recognized</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Derivative Liabilities Offset</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Cash Collateral Received</span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Net<br/>Amount</span></td></tr><tr><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Derivative assets</span></div></td><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">December 31, 2020</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">13,441</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(1,936)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(10,879)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">626</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">626</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">December 31, 2019</span></td><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">11,864 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(10,410)</span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(1,408)</span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">45 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">45 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:15pt"><td colspan="36" style="background-color:#ffffff;padding:0 1pt"/></tr><tr style="height:29pt"><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" rowspan="2" style="background-color:#00a94f;padding:0 1pt"/><td colspan="12" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross Amounts Subject to Master Netting Arrangements Offset on the Consolidated Balance Sheets</span></td><td colspan="3" rowspan="2" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Net Amounts Presented on the Consolidated Balance Sheets</span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" rowspan="2" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross Amounts Not Offset on the Consolidated Balance Sheets</span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/></tr><tr style="height:21pt"><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%"> ($ in Thousands)</span></td><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross Amounts Recognized</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Derivative Assets Offset</span></td><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Cash Collateral Pledged </span></td><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:0 1pt"/><td colspan="3" style="background-color:#00a94f;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#ffffff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Net<br/>Amount</span></td></tr><tr><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Derivative liabilities</span></div></td><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#dddddd;border-top:1pt solid #000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">December 31, 2020</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">27,951</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(1,936)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(25,625)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">390</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">390</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#dddddd;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">December 31, 2019</span></td><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">22,189 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(10,410)</span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(11,365)</span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">413 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#dddddd;padding:0 1pt"/><td colspan="2" style="background-color:#dddddd;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">413 </span></td><td style="background-color:#dddddd;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table>
CY2020Q4	asb	Lending Related Commitments Fair Value LendingRelatedCommitmentsFairValue	0	USD
CY2019Q4	asb	Lending Related Commitments Fair Value LendingRelatedCommitmentsFairValue	0	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	21907000	USD
CY2020	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	7000000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	47776000	USD
CY2020	asb	Expense Relatedto Qualified Affordable Housing Projects ExpenseRelatedtoQualifiedAffordableHousingProjects	23000000	USD
CY2019	asb	Expense Relatedto Qualified Affordable Housing Projects ExpenseRelatedtoQualifiedAffordableHousingProjects	19000000	USD
CY2018	asb	Expense Relatedto Qualified Affordable Housing Projects ExpenseRelatedtoQualifiedAffordableHousingProjects	17000000	USD
CY2020Q4	asb	Remaining Investmentin Qualified Affordable Housing Projects RemainingInvestmentinQualifiedAffordableHousingProjects	268000000	USD
CY2019Q4	asb	Remaining Investmentin Qualified Affordable Housing Projects RemainingInvestmentinQualifiedAffordableHousingProjects	234000000	USD
CY2020Q4	asb	Unfunded Equity Contributions Obligation Amount UnfundedEquityContributionsObligationAmount	118000000	USD
CY2019Q4	asb	Unfunded Equity Contributions Obligation Amount UnfundedEquityContributionsObligationAmount	123000000	USD
CY2020Q4	asb	Loans Repurchased Under Make Whole Requests LoansRepurchasedUnderMakeWholeRequests	10000000	USD
CY2019Q4	asb	Loans Repurchased Under Make Whole Requests LoansRepurchasedUnderMakeWholeRequests	2000000	USD
CY2020	asb	Loans Sold To Outside Investors Loss Reimbursement Settlement Paid LoansSoldToOutsideInvestorsLossReimbursementSettlementPaid	no
CY2019	asb	Loans Sold To Outside Investors Loss Reimbursement Settlement Paid LoansSoldToOutsideInvestorsLossReimbursementSettlementPaid	negligible
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CY2019Q4	asb	Mortgage Repurchase Reserve MortgageRepurchaseReserve	795000	USD
CY2020Q4	asb	Residential Mortgage Loans Sold With Recourse Risk ResidentialMortgageLoansSoldWithRecourseRisk	36000000	USD
CY2019Q4	asb	Residential Mortgage Loans Sold With Recourse Risk ResidentialMortgageLoansSoldWithRecourseRisk	39000000	USD
CY2020Q4	asb	Residential Mortgage Loans Sold With Credit Recourse Risk ResidentialMortgageLoansSoldWithCreditRecourseRisk	33000000	USD
CY2019Q4	asb	Residential Mortgage Loans Sold With Credit Recourse Risk ResidentialMortgageLoansSoldWithCreditRecourseRisk	45000000	USD
CY2020	asb	Fair Value Inputs Closing Ratio FairValueInputsClosingRatio	0.90
CY2020Q4	asb	Visa Restricted Stock Owned VisaRestrictedStockOwned	77996	shares
CY2020Q4	asb	Visa Class A Shares Current Conversion From Class B VisaClassASharesCurrentConversionFromClassB	126572	shares
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CY2019Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	278000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	306771000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	326790000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	333562000	USD
CY2020	us-gaap	Preferred Stock Dividends And Other Adjustments PreferredStockDividendsAndOtherAdjustments	18358000	USD
CY2019	us-gaap	Preferred Stock Dividends And Other Adjustments PreferredStockDividendsAndOtherAdjustments	15202000	USD
CY2018	us-gaap	Preferred Stock Dividends And Other Adjustments PreferredStockDividendsAndOtherAdjustments	10784000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	288413000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	311587000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	322779000	USD
CY2020	us-gaap	Dividends Common Stock DividendsCommonStock	111291000	USD
CY2019	us-gaap	Dividends Common Stock DividendsCommonStock	111091000	USD
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	104981000	USD
CY2020	asb	Unvested Share Based Payment Awards UnvestedShareBasedPaymentAwards	732000	USD
CY2019	asb	Unvested Share Based Payment Awards UnvestedShareBasedPaymentAwards	713000	USD
CY2018	asb	Unvested Share Based Payment Awards UnvestedShareBasedPaymentAwards	537000	USD
CY2020	us-gaap	Undistributed Earnings UndistributedEarnings	176390000	USD
CY2019	us-gaap	Undistributed Earnings UndistributedEarnings	199784000	USD
CY2018	us-gaap	Undistributed Earnings UndistributedEarnings	217260000	USD
CY2020	asb	Undistributed Earnings Allocated To Common Shareholders UndistributedEarningsAllocatedToCommonShareholders	175134000	USD
CY2019	asb	Undistributed Earnings Allocated To Common Shareholders UndistributedEarningsAllocatedToCommonShareholders	198424000	USD
CY2018	asb	Undistributed Earnings Allocated To Common Shareholders UndistributedEarningsAllocatedToCommonShareholders	216199000	USD
CY2020	asb	Undistributed Earnings Allocated To Unvested Share Based Payment Awards UndistributedEarningsAllocatedToUnvestedShareBasedPaymentAwards	1256000	USD
CY2019	asb	Undistributed Earnings Allocated To Unvested Share Based Payment Awards UndistributedEarningsAllocatedToUnvestedShareBasedPaymentAwards	1360000	USD
CY2018	asb	Undistributed Earnings Allocated To Unvested Share Based Payment Awards UndistributedEarningsAllocatedToUnvestedShareBasedPaymentAwards	1060000	USD
CY2020	asb	Undistributed Earnings Allocations UndistributedEarningsAllocations	176390000	USD
CY2019	asb	Undistributed Earnings Allocations UndistributedEarningsAllocations	199784000	USD
CY2018	asb	Undistributed Earnings Allocations UndistributedEarningsAllocations	217260000	USD
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CY2019	asb	Undistributed Earnings Basic UndistributedEarningsBasic	198424000	USD
CY2018	asb	Undistributed Earnings Basic UndistributedEarningsBasic	216199000	USD
CY2020	asb	Common Shareholders Earnings Basic CommonShareholdersEarningsBasic	286425000	USD
CY2019	asb	Common Shareholders Earnings Basic CommonShareholdersEarningsBasic	309514000	USD
CY2018	asb	Common Shareholders Earnings Basic CommonShareholdersEarningsBasic	321181000	USD
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CY2018	asb	Common Shareholders Earnings Diluted CommonShareholdersEarningsDiluted	321181000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	153005000	shares
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CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	637000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1398000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1985000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	0	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	0	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	402000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	153642000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	161932000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	169732000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.87
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.93
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.92
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.86
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.91
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.89
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	segment
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	762957000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	835674000	USD
CY2020	asb	Netintersegmentinterestincomeexpense Netintersegmentinterestincomeexpense	0	USD
CY2019	asb	Netintersegmentinterestincomeexpense Netintersegmentinterestincomeexpense	0	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	879580000	USD
CY2018	asb	Netintersegmentinterestincomeexpense Netintersegmentinterestincomeexpense	0	USD
CY2020	asb	Segmentnetinterestincome Segmentnetinterestincome	762957000	USD
CY2019	asb	Segmentnetinterestincome Segmentnetinterestincome	835674000	USD
CY2018	asb	Segmentnetinterestincome Segmentnetinterestincome	879580000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	514056000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	380824000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	355568000	USD
CY2020	us-gaap	Revenues Revenues	1277012000	USD
CY2019	us-gaap	Revenues Revenues	1216498000	USD
CY2018	us-gaap	Revenues Revenues	1235148000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	174006000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	16000000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	776034000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	793988000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	821799000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	326972000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	406509000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	413349000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	20200000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79720000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79786000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	306771000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	326790000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	333562000	USD
CY2020	asb	Allocated Goodwill Segment AllocatedGoodwillSegment	1109300000	USD
CY2019	asb	Allocated Goodwill Segment AllocatedGoodwillSegment	1176230000	USD
CY2018	asb	Allocated Goodwill Segment AllocatedGoodwillSegment	1169023000	USD
CY2020	asb	Tax Benefit From Tax Planning Strategies TaxBenefitFromTaxPlanningStrategies	63000000	USD
CY2020	asb	Noninterest Income In Scopeof Topic606 NoninterestIncomeInScopeofTopic606	246077000	USD
CY2019	asb	Noninterest Income In Scopeof Topic606 NoninterestIncomeInScopeofTopic606	288247000	USD
CY2018	asb	Noninterest Income In Scopeof Topic606 NoninterestIncomeInScopeofTopic606	290084000	USD
CY2020	asb	Noninterest Income Outsideof Scopeof Topic606 NoninterestIncomeOutsideofScopeofTopic606	267979000	USD
CY2019	asb	Noninterest Income Outsideof Scopeof Topic606 NoninterestIncomeOutsideofScopeofTopic606	92577000	USD
CY2018	asb	Noninterest Income Outsideof Scopeof Topic606 NoninterestIncomeOutsideofScopeofTopic606	65484000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	514056000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	380824000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	355568000	USD

Files In Submission

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$ASB
ASSOCIATED BANC-CORP Stock $asb

2019 Q4 Form 10-K Financial Statement

#000000778921000018 Filed on February 09, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ASB ASSOCIATED BANC-CORP Stock $asb

2019 Q4 Form 10-K Financial Statement

#000000778921000018 Filed on February 09, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ASB
ASSOCIATED BANC-CORP Stock $asb