$COLB
Columbia Banking System Inc Stock $colb

$colb Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-Q Financial Statement

#000088734319000151 Filed on November 06, 2019

Income Statement

Concept	2019 Q4	2019 Q3	2018 Q3
Revenue	$133.1M	$132.5M	$127.6M
YoY Change	2.55%	3.89%	41.27%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$5.102M	$4.466M
YoY Change		14.24%	8.35%
% of Gross Profit
Depreciation & Amortization	$8.000M	$8.900M	$9.000M
YoY Change	11.11%	-1.11%	20.0%
% of Gross Profit
Operating Expenses		$5.102M	$4.466M
YoY Change		14.24%	8.35%
Operating Profit
YoY Change
Interest Expense	$8.292M	$10.08M	$4.779M
YoY Change	40.23%	110.99%	247.82%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$58.03M	$63.11M	$57.82M
YoY Change	4.6%	9.14%	-2.18%
Income Tax	$11.90M	$12.38M	$11.41M
% Of Pretax Income	20.51%	19.61%	19.73%
Net Earnings	$46.13M	$50.73M	$46.42M
YoY Change	3.09%	9.29%	13.85%
Net Earnings / Revenue	34.66%	38.27%	36.38%
Basic Earnings Per Share	$0.64	$0.70	$0.63
Diluted Earnings Per Share	$0.64	$0.70	$0.63
COMMON SHARES
Basic Shares Outstanding	72.14M shares	71.80M shares	72.43M shares
Diluted Shares Outstanding		71.80M shares	72.43M shares

Balance Sheet

Concept	2019 Q4	2019 Q3	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$247.7M	$298.6M	$242.2M
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	$165.4M	$165.4M	$169.7M
YoY Change	-2.0%	-2.5%	18.37%
Goodwill	$765.8M	$765.8M	$765.8M
YoY Change	0.0%	0.0%	100.08%
Intangibles	$35.46M	$37.91M	$48.83M
YoY Change	-22.81%	-22.36%	252.67%
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$14.08B	$13.76B	$12.96B
YoY Change	7.52%	6.18%	32.01%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$63.00M	$57.00M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$64.00M	$24.00M	$62.00M
YoY Change	4.92%	-61.29%	51.22%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$63.00M	$57.00M	$62.00M
YoY Change	3.28%	-8.06%	51.22%
LONG-TERM LIABILITIES
Long-Term Debt	$35.00M	$35.00M	$36.00M
YoY Change	0.0%	-2.78%
Other Long-Term Liabilities	$119.0M	$131.0M	$107.0M
YoY Change	11.21%	22.43%	10.31%
Total Long-Term Liabilities	$154.0M	$166.0M	$143.0M
YoY Change	8.45%	16.08%	47.42%
TOTAL LIABILITIES
Total Short-Term Liabilities	$63.00M	$57.00M	$62.00M
Total Long-Term Liabilities	$154.0M	$166.0M	$143.0M
Total Liabilities	$11.92B	$11.60B	$10.98B
YoY Change	7.76%	5.66%	29.33%
SHAREHOLDERS EQUITY
Retained Earnings	$519.7M	$493.7M	$411.3M
YoY Change	21.79%	20.05%	24.45%
Common Stock	$1.651B	$1.648B	$1.640B
YoY Change	0.52%	0.5%	63.38%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$50.83M	$45.38M
YoY Change
Treasury Stock Shares	1.453M shares	1.300M shares
Shareholders Equity	$2.160B	$2.162B	$1.981B
YoY Change
Total Liabilities & Shareholders Equity	$14.08B	$13.76B	$12.96B
YoY Change	7.52%	6.18%	32.01%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2018 Q3
OPERATING ACTIVITIES
Net Income	$46.13M	$50.73M	$46.42M
YoY Change	3.09%	9.29%	13.85%
Depreciation, Depletion And Amortization	$8.000M	$8.900M	$9.000M
YoY Change	11.11%	-1.11%	20.0%
Cash From Operating Activities	$49.90M	$56.30M	$56.70M
YoY Change	-24.39%	-0.71%	31.25%
INVESTING ACTIVITIES
Capital Expenditures	-$2.600M	-$2.300M	-$3.300M
YoY Change	-13.33%	-30.3%	32.0%
Acquisitions
YoY Change
Other Investing Activities	-$402.7M	-$586.9M	-$360.0M
YoY Change	377.7%	63.03%	3770.97%
Cash From Investing Activities	-$405.4M	-$589.2M	-$363.2M
YoY Change	363.84%	62.22%	2977.97%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	304.5M	572.8M	285.1M
YoY Change	436.09%	100.91%	259.97%
NET CHANGE
Cash From Operating Activities	49.90M	56.30M	56.70M
Cash From Investing Activities	-405.4M	-589.2M	-363.2M
Cash From Financing Activities	304.5M	572.8M	285.1M
Net Change In Cash	-51.00M	39.90M	-21.40M
YoY Change	-244.07%	-286.45%	-119.35%
FREE CASH FLOW
Cash From Operating Activities	$49.90M	$56.30M	$56.70M
Capital Expenditures	-$2.600M	-$2.300M	-$3.300M
Free Cash Flow	$52.50M	$58.60M	$60.00M
YoY Change	-23.91%	-2.33%	31.29%

Facts In Submission

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	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
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	dei	Entity File Number EntityFileNumber	0-20288
	dei	Entity Registrant Name EntityRegistrantName	COLUMBIA BANKING SYSTEM, INC.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	WA
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	91-1422237
	dei	Entity Address Address Line1 EntityAddressAddressLine1	1301 A Street
	dei	Entity Address City Or Town EntityAddressCityOrTown	Tacoma
	dei	Entity Address State Or Province EntityAddressStateOrProvince	WA
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	dei	City Area Code CityAreaCode	253
	dei	Local Phone Number LocalPhoneNumber	305-1900
	dei	Security12b Title Security12bTitle	Common Stock, No Par Value
	dei	Trading Symbol TradingSymbol	COLB
	dei	Security Exchange Name SecurityExchangeName	NASDAQ
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CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	122450000	USD
CY2018Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	122796000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	368588000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	354951000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	299000	USD
CY2018Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3153000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1879000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	12980000	USD
CY2019Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	122151000	USD
CY2018Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	119643000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	366709000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	341971000	USD
CY2019Q3	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	9015000	USD
	colb	Cardrevenue Cardrevenue	11431000	USD
	colb	Cardrevenue Cardrevenue	16143000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	9608000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	8924000	USD
CY2018Q3	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	9266000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	27030000	USD
CY2019Q3	us-gaap	Professional Fees ProfessionalFees	5683000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	26689000	USD
CY2019Q3	colb	Cardrevenue Cardrevenue	4006000	USD
CY2018Q3	colb	Cardrevenue Cardrevenue	3714000	USD
CY2019Q3	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	3226000	USD
CY2018Q3	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	2975000	USD
CY2019Q3	colb	Loanrevenue Loanrevenue	3855000	USD
CY2018Q3	colb	Loanrevenue Loanrevenue	3282000	USD
	colb	Loanrevenue Loanrevenue	9840000	USD
	colb	Loanrevenue Loanrevenue	9522000	USD
CY2019Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1528000	USD
CY2018Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1402000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	4644000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	4540000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	0	USD
CY2018Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-62000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	2132000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-73000	USD
CY2019Q3	us-gaap	Noninterest Income Other NoninterestIncomeOther	6400000	USD
CY2018Q3	us-gaap	Noninterest Income Other NoninterestIncomeOther	442000	USD
	us-gaap	Noninterest Income Other NoninterestIncomeOther	10689000	USD
	us-gaap	Noninterest Income Other NoninterestIncomeOther	2109000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	28030000	USD
CY2018Q3	us-gaap	Noninterest Income NoninterestIncome	21019000	USD
	us-gaap	Noninterest Income NoninterestIncome	75374000	USD
	us-gaap	Noninterest Income NoninterestIncome	67854000	USD
CY2019Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	54459000	USD
CY2018Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	49419000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	158559000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	148938000	USD
CY2019Q3	us-gaap	Occupancy Net OccupancyNet	8645000	USD
CY2018Q3	us-gaap	Occupancy Net OccupancyNet	8321000	USD
	us-gaap	Occupancy Net OccupancyNet	26166000	USD
	us-gaap	Occupancy Net OccupancyNet	27718000	USD
CY2019Q3	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	5102000	USD
CY2018Q3	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	4466000	USD
	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	14372000	USD
	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	14957000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9346000	USD
CY2019Q3	colb	Taxes Licenses And Fees TaxesLicensesAndFees	1325000	USD
CY2018Q3	us-gaap	Professional Fees ProfessionalFees	4695000	USD
CY2018Q3	colb	Taxes Licenses And Fees TaxesLicensesAndFees	1478000	USD
	colb	Taxes Licenses And Fees TaxesLicensesAndFees	4612000	USD
	us-gaap	Professional Fees ProfessionalFees	16810000	USD
	us-gaap	Professional Fees ProfessionalFees	12103000	USD
CY2019Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2632000	USD
CY2018Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3070000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	8029000	USD
	colb	Taxes Licenses And Fees TaxesLicensesAndFees	4254000	USD
CY2019Q3	us-gaap	Advertising Expense AdvertisingExpense	1752000	USD
CY2018Q3	us-gaap	Advertising Expense AdvertisingExpense	1472000	USD
	us-gaap	Advertising Expense AdvertisingExpense	3596000	USD
	us-gaap	Advertising Expense AdvertisingExpense	4523000	USD
CY2019Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	-38000	USD
CY2018Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	904000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1902000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	2778000	USD
CY2019Q3	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	-90000	USD
CY2018Q3	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	485000	USD
	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	-682000	USD
	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	1244000	USD
CY2019Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	7606000	USD
CY2018Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	8531000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	25140000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	27610000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	87076000	USD
CY2018Q3	us-gaap	Noninterest Expense NoninterestExpense	82841000	USD
	us-gaap	Noninterest Expense NoninterestExpense	258504000	USD
	us-gaap	Noninterest Expense NoninterestExpense	253471000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	63105000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	57821000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	183579000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	156354000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12378000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11406000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	35257000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	28220000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	50727000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	46415000	USD
	us-gaap	Net Income Loss NetIncomeLoss	148322000	USD
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.75
	us-gaap	Net Income Loss NetIncomeLoss	128134000	USD
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.63
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.04
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.75
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.04
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	71803000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72427000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72256000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72370000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	71803000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72432000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72257000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72374000	shares
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	50727000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	46415000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	14593000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-14149000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	14593000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-14149000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	62000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	61000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-62000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-61000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	3137000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-58000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	3079000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	17734000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-14088000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	68461000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	32327000	USD
	us-gaap	Net Income Loss NetIncomeLoss	148322000	USD
	us-gaap	Net Income Loss NetIncomeLoss	128134000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	86519000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-48043000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	1636000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	81000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	84883000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-48124000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	184000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	183000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-184000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-183000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	15180000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	0	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-58000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	0	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	15122000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	0	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	100189000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-47941000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	248511000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	80193000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	2133638000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	50727000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	17734000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	1132000	USD
CY2019Q3	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	1000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2299000	USD
CY2019Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	19000	USD
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	20418000	USD
CY2019Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	23517000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	2161577000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2033649000	USD
	us-gaap	Net Income Loss NetIncomeLoss	148322000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	100189000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	2025000	USD
	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	2000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	6827000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2765000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	82074000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	45380000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	2161577000	USD
CY2018Q2	us-gaap	Stockholders Equity StockholdersEquity	1964881000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	46415000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-14088000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	1121000	USD
CY2018Q3	colb	Stock Adjustment Deferred Compensation Shares StockAdjustmentDeferredCompensationShares	0	shares
CY2018Q3	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	1000	USD
CY2018Q3	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	1000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2148000	USD
CY2018Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	33000	USD
CY2018Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	19050000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	1981395000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	1949922000	USD
	us-gaap	Net Income Loss NetIncomeLoss	128134000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-47941000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	1857000	USD
	colb	Stock Adjustment Deferred Compensation Shares StockAdjustmentDeferredCompensationShares	0	shares
	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	7000	USD
	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	7000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	6231000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2660000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	54155000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	1981395000	USD
	us-gaap	Net Income Loss NetIncomeLoss	148322000	USD
	us-gaap	Net Income Loss NetIncomeLoss	128134000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1879000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	12980000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	6827000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	6231000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	26150000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	25807000	USD
	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	2132000	USD
	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	-73000	USD
	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	6787000	USD
	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	-142000	USD
	colb	Netgainlossonsaleandvaluationadjustmentsof Oreo NetgainlossonsaleandvaluationadjustmentsofOREO	602000	USD
	colb	Netgainlossonsaleandvaluationadjustmentsof Oreo NetgainlossonsaleandvaluationadjustmentsofOREO	-1299000	USD
	colb	Gainonbankownedlifeinsurancedeathbenefit Gainonbankownedlifeinsurancedeathbenefit	2975000	USD
	colb	Gainonbankownedlifeinsurancedeathbenefit Gainonbankownedlifeinsurancedeathbenefit	0	USD
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	134634000	USD
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	103614000	USD
	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	123447000	USD
	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	104105000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	3180000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	7595000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	632000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	618000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	31840000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2599000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	154813000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	171243000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	29706000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	5662000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	305581000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	121413000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	649133000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	606052000	USD
	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	57075000	USD
	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	46969000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	5833000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	8253000	USD
	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	190800000	USD
	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	136120000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	259554000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	32330000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	287479000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	311956000	USD
	us-gaap	Proceeds From Sales Of Assets Investing Activities ProceedsFromSalesOfAssetsInvestingActivities	7735000	USD
	us-gaap	Proceeds From Sales Of Assets Investing Activities ProceedsFromSalesOfAssetsInvestingActivities	14956000	USD
	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	187080000	USD
	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	129920000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	6433000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	5868000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	5074000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-460141000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-418703000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	397893000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	72151000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-36605000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	8138000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	4770000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	3403000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	36000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	5010000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	100000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2025000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	1857000	USD
	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	4677000000	USD
	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	3248000000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	36000000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	5010000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	100000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	USD
	colb	Repaymentsofjuniorsubordinateddebt Repaymentsofjuniorsubordinateddebt	0	USD
	colb	Repaymentsofjuniorsubordinateddebt Repaymentsofjuniorsubordinateddebt	8248000	USD
	colb	Repaymentoftermrepurchaseagreement Repaymentoftermrepurchaseagreement	0	USD
	colb	Repaymentoftermrepurchaseagreement Repaymentoftermrepurchaseagreement	25000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	81822000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	54149000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	45380000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2765000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2660000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	326346000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	147089000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	21018000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-100371000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	277587000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	342533000	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	298605000	USD
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	242162000	USD
	us-gaap	Interest Paid Net InterestPaidNet	27623000	USD
	us-gaap	Interest Paid Net InterestPaidNet	11699000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	33134000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	12768000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	386000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	1200000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	152000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	464000	USD
	colb	Changeindividendspayableonunvestedshares Changeindividendspayableonunvestedshares	252000	USD
	colb	Changeindividendspayableonunvestedshares Changeindividendspayableonunvestedshares	6000	USD
	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	<div style="line-height:120%;padding-top:12px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-style:italic;">Recently Issued Accounting Standards, Not Yet Adopted</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In April 2019, the FASB issued ASU 2019-04, </span><span style="font-family:inherit;font-size:10pt;font-style:italic;">Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments</span><span style="font-family:inherit;font-size:10pt;">. The amendments in this ASU clarify certain aspects of accounting for credit losses, hedging activities, and financial instruments (addressed by ASUs 2016-01, 2016-13, and 2017-12). Many of the amendments reflect decisions reached at FASB meetings or meetings of the Board’s credit losses transition resource group. Topics covered in this ASU include: accrued interest, transfers between classifications or categories for loans and debt securities, recoveries, reinsurance recoverables, projections of interest rate environments for variable-rate financial instruments, costs to sell when foreclosure is probable, consideration of expected prepayments when determining the effective interest rate, vintage disclosures, extension and renewal options, etc. The amendments in ASU 2019-04 are effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years. Early adoption is permitted, including adoption in any interim period. The Company is assessing the impact that this guidance will have on its Consolidated Financial Statements.</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In June 2016, the FASB issued ASU 2016-13, </span><span style="font-family:inherit;font-size:10pt;font-style:italic;">Measurement of Credit Losses on Financial Instruments</span><span style="font-family:inherit;font-size:10pt;">. The amendments included in this ASU require an entity to reflect its current estimate of all expected credit losses for assets held at an amortized cost basis. For available for sale debt securities, credit losses will be measured in a manner similar to current GAAP, however, this ASU will require that credit losses be presented as an allowance rather than as a write-down. The amendments in ASU 2016-13 are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and are required to be adopted through a modified retrospective approach, with a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the ASU is effective.</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Unlike the incurred loss models in existing GAAP, the CECL model in ASU 2016-13 does not specify a threshold for the recognition of an impairment allowance. Rather, the Company will recognize an impairment allowance equal to its estimate of lifetime expected credit losses, adjusted for prepayments, for in-scope financial instruments as of the end of the reporting period. Accordingly, the impairment allowance measured under the CECL model could change significantly from the impairment allowance measured under the Company’s existing incurred loss model. The Company has engaged a third-party vendor to assist in the CECL calculation and has developed an internal governance framework to oversee the CECL implementation. Significant CECL implementation matters that have been completed include identifying, sourcing and storing data, addressing data gaps, defining a reasonable and supportable forecast period and selecting historical loss information. Other significant CECL implementation matters being addressed by the Company include selecting loss estimation methodologies, assessing the impact to internal controls over financial reporting, and capital planning.</span></div><div style="line-height:120%;padding-top:12px;text-align:left;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Upon adoption of the standard on January 1, 2020, the Company expects that, based on current expectations of future economic conditions, its impact on the allowance for credit losses will range from a decrease of </span><span style="font-family:inherit;font-size:10pt;"><span>10%</span></span><span style="font-family:inherit;font-size:10pt;"> to an increase of </span><span style="font-family:inherit;font-size:10pt;"><span>5%</span></span><span style="font-family:inherit;font-size:10pt;">, with no material impact on capital levels anticipated. The ultimate impact will depend on the characteristics of the Company’s portfolios as well as the macroeconomic conditions and forecasts upon adoption, the ultimate validation of models and methodologies, and other management judgments.</span></div>
CY2019Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3300143000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	79026000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	11597000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3367572000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3210615000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	12799000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	55966000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3167448000	USD
CY2019Q3	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	USD
CY2018Q3	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	259554000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	32330000	USD
CY2019Q3	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	0	USD
CY2018Q3	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	0	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	3357000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	235000	USD
CY2019Q3	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	0	USD
CY2018Q3	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	0	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	1225000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	129000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	0	USD
CY2018Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-62000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	0	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-179000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	0	USD
CY2018Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-62000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	2132000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-73000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	112412000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	112594000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	412269000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	416294000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1592778000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1650631000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	1182684000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	1188053000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3300143000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3367572000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	710468000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	531453000	USD
CY2019Q3	colb	Availableforsale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Loss Instant AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLossInstant	4272000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	616089000	USD
CY2019Q3	colb	Availableforsale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Lossinstant AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLossinstant	7325000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	1147542000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	11597000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	276306000	USD
CY2018Q4	colb	Availableforsale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Loss Instant AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLossInstant	1598000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	1873565000	USD
CY2018Q4	colb	Availableforsale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Lossinstant AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLossinstant	54368000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	2149871000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	55966000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	35455000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	42194000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	8756355000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	8391511000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	82660000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83369000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	8673695000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	8308142000	USD
CY2019Q3	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	15036000	USD
CY2018Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	3849000	USD
CY2019Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	37021000	USD
CY2019Q3	colb	Financing Receivable Unpaid Principal Balance Nonaccrual Status FinancingReceivableUnpaidPrincipalBalanceNonaccrualStatus	48126000	USD
CY2018Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	54842000	USD
CY2018Q4	colb	Financing Receivable Unpaid Principal Balance Nonaccrual Status FinancingReceivableUnpaidPrincipalBalanceNonaccrualStatus	65358000	USD
CY2019Q3	colb	Financing Receivable Modifications Additional Commitment To Lend FinancingReceivableModificationsAdditionalCommitmentToLend	1500000	USD
CY2018Q4	colb	Financing Receivable Modifications Additional Commitment To Lend FinancingReceivableModificationsAdditionalCommitmentToLend	2100000	USD
	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1
	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	26000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	20989000	USD
CY2018Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	25350000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	21949000	USD
CY2017Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	31176000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	1289000	USD
CY2018Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	2233000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	4865000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	6435000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	45000	USD
CY2018Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	221000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	-61000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	387000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	719000	USD
CY2018Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	279000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	3229000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	-1179000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	20374000	USD
CY2018Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	23175000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	20374000	USD
CY2018Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	23175000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80517000	USD
CY2019Q3	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	3372000	USD
CY2019Q3	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	5216000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	299000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	82660000	USD
CY2019Q3	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	2326000	USD
CY2019Q3	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	80334000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83369000	USD
	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	11647000	USD
	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	9059000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1879000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	82660000	USD
CY2019Q3	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	2326000	USD
CY2019Q3	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	80334000	USD
CY2018Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80150000	USD
CY2018Q3	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	2091000	USD
CY2018Q3	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	2575000	USD
CY2018Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3153000	USD
CY2018Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83787000	USD
CY2018Q3	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	1255000	USD
CY2018Q3	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	82532000	USD
CY2017Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	75646000	USD
	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	13640000	USD
	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	8801000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	12980000	USD
CY2018Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83787000	USD
CY2018Q3	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	1255000	USD
CY2018Q3	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	82532000	USD
CY2019Q2	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3980000	USD
CY2018Q2	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3680000	USD
CY2018Q4	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	4330000	USD
CY2017Q4	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3130000	USD
CY2019Q3	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	-400000	USD
CY2018Q3	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	275000	USD
	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	-750000	USD
	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	825000	USD
CY2019Q3	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3580000	USD
CY2018Q3	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3955000	USD
CY2019Q3	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3580000	USD
CY2018Q3	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3955000	USD
CY2019Q2	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	1118000	USD
CY2018Q2	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	7080000	USD
CY2018Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	6019000	USD
CY2017Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	13298000	USD
CY2019Q3	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	0	USD
CY2018Q3	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	794000	USD
	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	386000	USD
	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	1200000	USD
CY2019Q3	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	0	USD
CY2018Q3	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	495000	USD
	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	195000	USD
	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	697000	USD
CY2019Q3	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	588000	USD
CY2018Q3	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	47000	USD
	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	6382000	USD
	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	5868000	USD
CY2019Q3	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	95000	USD
CY2018Q3	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-1000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	797000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-602000	USD
CY2019Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	625000	USD
CY2018Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	7331000	USD
CY2019Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	625000	USD
CY2018Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	7331000	USD
CY2019Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	1300000	USD
CY2019Q3	us-gaap	Goodwill Goodwill	765842000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	765842000	USD
CY2019Q3	us-gaap	Goodwill Goodwill	765842000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	765842000	USD
CY2019Q3	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2018Q3	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2019Q3	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2018Q3	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2019Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	37908000	USD
CY2018Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	48827000	USD
CY2019Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	37908000	USD
CY2018Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	48827000	USD
CY2019Q3	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	803750000	USD
CY2018Q3	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	814669000	USD
CY2019Q3	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	803750000	USD
CY2018Q3	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	814669000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	2451000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	8724000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	7264000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	5880000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	4552000	USD
CY2019Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	51295000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	57196000	USD
CY2019Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y6M
CY2019Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.031
CY2019Q3	us-gaap	Operating Lease Payments OperatingLeasePayments	2800000	USD
CY2019Q3	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	9200000	USD
CY2019Q3	us-gaap	Operating Lease Cost OperatingLeaseCost	2700000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	8285000	USD
CY2019Q3	us-gaap	Variable Lease Cost VariableLeaseCost	487000	USD
	us-gaap	Variable Lease Cost VariableLeaseCost	1510000	USD
CY2019Q3	us-gaap	Sublease Income SubleaseIncome	297000	USD
	us-gaap	Sublease Income SubleaseIncome	918000	USD
CY2019Q3	us-gaap	Lease Cost LeaseCost	2890000	USD
	us-gaap	Lease Cost LeaseCost	8877000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	2717000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	10619000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	10376000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	9795000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	8546000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	22685000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	64738000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	7542000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	57196000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	10947000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	9766000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	8729000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	8102000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	6796000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	18703000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	63043000	USD
CY2019Q3	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	30000000.0	USD
CY2019Q3	us-gaap	Interest Rate Cash Flow Hedge Gain Loss To Be Reclassified During Next12 Months Net InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet	3100000	USD
CY2019Q3	us-gaap	Gain Loss On Derivative Instruments Net Pretax GainLossOnDerivativeInstrumentsNetPretax	0	USD
CY2019Q3	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	4088000	USD
CY2018Q3	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	76000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	0	USD
	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	19779000	USD
	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	0	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	76000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	0	USD
CY2019Q3	colb	Repurchaseagreementsamountsoffsetinbalancesheet Repurchaseagreementsamountsoffsetinbalancesheet	0	USD
CY2019Q3	colb	Repurchaseagreementsnetamountpresentedinstatementoffinancialposition Repurchaseagreementsnetamountpresentedinstatementoffinancialposition	24489000	USD
CY2019Q3	us-gaap	Securities Sold Under Agreements To Repurchase Collateral Right To Reclaim Securities SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimSecurities	24489000	USD
CY2019Q3	colb	Securitiessoldunderagreementstorepurchaseamountnotoffset Securitiessoldunderagreementstorepurchaseamountnotoffset	0	USD
CY2018Q4	colb	Repurchaseagreementsamountsoffsetinbalancesheet Repurchaseagreementsamountsoffsetinbalancesheet	0	USD
CY2018Q4	colb	Repurchaseagreementsnetamountpresentedinstatementoffinancialposition Repurchaseagreementsnetamountpresentedinstatementoffinancialposition	61094000	USD
CY2018Q4	us-gaap	Securities Sold Under Agreements To Repurchase Collateral Right To Reclaim Securities SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimSecurities	61094000	USD
CY2018Q4	colb	Securitiessoldunderagreementstorepurchaseamountnotoffset Securitiessoldunderagreementstorepurchaseamountnotoffset	0	USD
CY2019Q3	us-gaap	Secured Borrowings Gross Including Not Subject To Master Netting Arrangement SecuredBorrowingsGrossIncludingNotSubjectToMasterNettingArrangement	24489000	USD
CY2019Q3	us-gaap	Secured Borrowings Gross Difference Amount SecuredBorrowingsGrossDifferenceAmount	0	USD
CY2019Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2019Q1	colb	Common Stock Special Cash Dividends Per Share Declared CommonStockSpecialCashDividendsPerShareDeclared	0.14
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2019Q2	colb	Common Stock Special Cash Dividends Per Share Declared CommonStockSpecialCashDividendsPerShareDeclared	0.14
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2019Q3	colb	Common Stock Special Cash Dividends Per Share Declared CommonStockSpecialCashDividendsPerShareDeclared	0
CY2019Q3	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	676000	shares
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1300000	shares
CY2019Q3	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	34.77
	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	34.89
CY2019Q3	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	1600000	shares
CY2019Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	47150000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	17730000	USD
CY2019Q3	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-4000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	17734000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	64884000	USD
CY2018Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-55921000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-14149000	USD
CY2018Q3	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-61000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-14088000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-70009000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-35305000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	101699000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1510000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	100189000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	64884000	USD
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-22225000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-48043000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-102000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-47941000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-70009000	USD
CY2019Q3	us-gaap	Fair Value Liabilities Level1 To Level2 Transfers Amount FairValueLiabilitiesLevel1ToLevel2TransfersAmount	0	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	50727000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	46415000	USD
	us-gaap	Net Income Loss NetIncomeLoss	148322000	USD
	us-gaap	Net Income Loss NetIncomeLoss	128134000	USD
CY2019Q3	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	358000	USD
CY2018Q3	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	504000	USD
	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	1204000	USD
	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	1413000	USD
CY2019Q3	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	50369000	USD
CY2018Q3	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	45911000	USD
	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	147118000	USD
	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	126721000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	71803000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72427000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72256000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72370000	shares
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.63
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.04
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.75
CY2019Q3	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	50369000	USD
CY2018Q3	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	45911000	USD
	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	147118000	USD
	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	126721000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	71803000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72427000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72256000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72370000	shares
CY2019Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2018Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	5000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	4000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	71803000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72432000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72257000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72374000	shares
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.04
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.75
CY2019Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	5000	shares
CY2019Q3	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	9015000	USD
CY2018Q3	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	9266000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	27030000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	26689000	USD
CY2019Q3	colb	Cardrevenue Cardrevenue	4006000	USD
CY2018Q3	colb	Cardrevenue Cardrevenue	3714000	USD
	colb	Cardrevenue Cardrevenue	11431000	USD
	colb	Cardrevenue Cardrevenue	16143000	USD
CY2019Q3	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	3226000	USD
CY2018Q3	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	2975000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	9608000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	8924000	USD
CY2019Q3	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	16247000	USD
CY2018Q3	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	15955000	USD
	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	48069000	USD
	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	51756000	USD
CY2019Q3	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	11783000	USD
CY2018Q3	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	5064000	USD
	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	27305000	USD
	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	16098000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	28030000	USD
CY2018Q3	us-gaap	Noninterest Income NoninterestIncome	21019000	USD
	us-gaap	Noninterest Income NoninterestIncome	75374000	USD
	us-gaap	Noninterest Income NoninterestIncome	67854000	USD

Files In Submission

Name	View Source	Status
0000887343-19-000151-index-headers.html	Edgar Link	pending
0000887343-19-000151-index.html	Edgar Link	pending
0000887343-19-000151.txt	Edgar Link	pending
0000887343-19-000151-xbrl.zip	Edgar Link	pending
colb-20190930.xsd	Edgar Link	pending
colb-20190930_cal.xml	Edgar Link	unprocessable
colb-20190930_def.xml	Edgar Link	unprocessable
colb-20190930_lab.xml	Edgar Link	unprocessable
colb-20190930_pre.xml	Edgar Link	unprocessable
colb3q2019ex311.htm	Edgar Link	pending
colb3q2019ex312.htm	Edgar Link	pending
colb3q2019ex32.htm	Edgar Link	pending
colb3q2019form10-q.htm	Edgar Link	pending
colb3q2019form10-q_htm.xml	Edgar Link	completed
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
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R8.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$COLB
Columbia Banking System Inc Stock $colb

2019 Q4 Form 10-Q Financial Statement

#000088734319000151 Filed on November 06, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$COLB Columbia Banking System Inc Stock $colb

2019 Q4 Form 10-Q Financial Statement

#000088734319000151 Filed on November 06, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$COLB
Columbia Banking System Inc Stock $colb