$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal

$wal Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000121254524000092 Filed on February 28, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$1.055B		$98.60M
YoY Change	8.89%		-96.34%
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	$19.10M	$49.50M
YoY Change	26.06%	17.18%	55.66%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$456.1M		$1.696B
YoY Change	27.05%		256.76%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$231.8M	$211.0M	$933.6M
YoY Change	25.57%	-42.14%	-29.06%
Income Tax	$54.40M	$63.10M	$211.2M
% Of Pretax Income	23.47%	29.91%	22.62%
Net Earnings	$174.2M	$144.7M	$709.6M
YoY Change	25.32%	-50.07%	-32.06%
Net Earnings / Revenue	16.51%		719.68%
Basic Earnings Per Share	$1.61		$6.55
Diluted Earnings Per Share	$1.60	$1.33	$6.54
COMMON SHARES
Basic Shares Outstanding	110.2M shares	109.5M shares	108.3M shares
Diluted Shares Outstanding	109.0M shares		108.5M shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$3.550B	$1.576B
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	$483.0M	$484.0M	$484.0M
YoY Change	7.57%	10.25%	10.25%
Goodwill		$527.0M
YoY Change		0.0%
Intangibles
YoY Change
Long-Term Investments	$130.0M	$126.0M	$126.0M
YoY Change	-7.8%	-21.25%	-21.25%
Other Assets	$300.0M	$287.0M	$287.0M
YoY Change	3.81%	-7.72%	-7.72%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$76.99B	$70.86B	$70.86B
YoY Change	8.36%	4.62%	4.62%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$1.300B	$1.147B	$1.147B
YoY Change	29.1%	-15.48%	-15.48%
Accrued Expenses	$172.0M	$179.0M	$179.0M
YoY Change	-6.52%	-3.24%	-3.24%
Deferred Revenue
YoY Change
Short-Term Debt	$5.780B	$6.784B	$584.0M
YoY Change	-61.0%	35.9%	-15.61%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$1.472B	$1.326B	$1.326B
YoY Change	23.59%	-14.01%	-14.01%
LONG-TERM LIABILITIES
Long-Term Debt	$7.117B	$8.125B	$8.125B
YoY Change	-57.51%	12.97%	12.97%
Other Long-Term Liabilities	$1.300B	$1.147B	$1.147B
YoY Change	29.1%	-15.48%	-15.48%
Total Long-Term Liabilities	$7.117B	$8.125B	$8.125B
YoY Change	-57.51%	12.97%	12.97%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.472B	$1.326B	$1.326B
Total Long-Term Liabilities	$7.117B	$8.125B	$8.125B
Total Liabilities	$70.82B	$64.78B	$64.78B
YoY Change	8.07%	3.86%	3.86%
SHAREHOLDERS EQUITY
Retained Earnings	$4.348B	$4.215B
YoY Change	15.52%	15.04%
Common Stock	$2.211B	$2.197B
YoY Change	1.89%	1.57%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$124.0M	$116.0M
YoY Change	6.9%	10.48%
Treasury Stock Shares
Shareholders Equity	$6.172B	$6.078B	$6.078B
YoY Change
Total Liabilities & Shareholders Equity	$76.99B	$70.86B	$70.86B
YoY Change	8.36%	4.62%	4.62%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$174.2M	$144.7M	$709.6M
YoY Change	25.32%	-50.07%	-32.06%
Depreciation, Depletion And Amortization	$20.80M	$19.10M	$49.50M
YoY Change	26.06%	17.18%	55.66%
Cash From Operating Activities	-$306.5M	$341.2M	-$328.6M
YoY Change	-14.22%	-57.05%	-114.64%
INVESTING ACTIVITIES
Capital Expenditures	$18.80M	$27.30M	$114.3M
YoY Change	-34.04%	-51.94%	-18.94%
Acquisitions			$0.00
YoY Change			-100.0%
Other Investing Activities	-$3.629B	-$1.853B	-$2.045B
YoY Change	175.21%	-438.29%	-84.26%
Cash From Investing Activities	-$3.648B	-$1.880B	-$2.159B
YoY Change	-370.78%	-482.99%	-83.56%
FINANCING ACTIVITIES
Cash Dividend Paid	$43.90M		$171.5M
YoY Change	3.05%		3.19%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net	$5.400M		$818.1M
YoY Change	-97.9%		2564.82%
Cash From Financing Activities	$5.928B	-382.0M	$3.020B
YoY Change	65.32%	-79.37%	-73.53%
NET CHANGE
Cash From Operating Activities	-$306.5M	341.2M	-$328.6M
Cash From Investing Activities	-$3.648B	-1.880B	-$2.159B
Cash From Financing Activities	$5.928B	-382.0M	$3.020B
Net Change In Cash	$1.974B	-1.921B	$532.7M
YoY Change	-23.96%	239.32%	1.08%
FREE CASH FLOW
Cash From Operating Activities	-$306.5M	$341.2M	-$328.6M
Capital Expenditures	$18.80M	$27.30M	$114.3M
Free Cash Flow	-$325.3M	$313.9M	-$442.9M
YoY Change	-15.68%	-57.44%	-121.05%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2022	us-gaap	General Insurance Expense GeneralInsuranceExpense	31100000	usd
CY2021	us-gaap	General Insurance Expense GeneralInsuranceExpense	23000000.0	usd
CY2023	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	122000000.0	usd
CY2022	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	83000000.0	usd
CY2021	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	58200000	usd
CY2023	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	107200000	usd
CY2022	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	99900000	usd
CY2021	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	58600000	usd
CY2023	us-gaap	Occupancy Net OccupancyNet	65600000	usd
CY2022	us-gaap	Occupancy Net OccupancyNet	55500000	usd
CY2021	us-gaap	Occupancy Net OccupancyNet	43800000	usd
CY2023	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	58800000	usd
CY2022	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	55500000	usd
CY2021	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	53500000	usd
CY2023	us-gaap	Business Development BusinessDevelopment	21800000	usd
CY2022	us-gaap	Business Development BusinessDevelopment	22100000	usd
CY2021	us-gaap	Business Development BusinessDevelopment	13500000	usd
CY2023	us-gaap	Loan Processing Fee LoanProcessingFee	20400000	usd
CY2022	us-gaap	Loan Processing Fee LoanProcessingFee	23100000	usd
CY2021	us-gaap	Loan Processing Fee LoanProcessingFee	28800000	usd
CY2023	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	0	usd
CY2022	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	400000	usd
CY2021	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	15300000	usd
CY2023	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	52700000	usd
CY2023	us-gaap	Other Noninterest Expense OtherNoninterestExpense	86900000	usd
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	80800000	usd
CY2021	us-gaap	Other Noninterest Expense OtherNoninterestExpense	54300000	usd
CY2022	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	usd
CY2021	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-5900000	usd
CY2023	us-gaap	Noninterest Expense NoninterestExpense	1623400000	usd
CY2022	us-gaap	Noninterest Expense NoninterestExpense	1156700000	usd
CY2021	us-gaap	Noninterest Expense NoninterestExpense	851400000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	933600000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1316100000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1123000000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	211200000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	258800000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	223800000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1057300000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	899200000	usd
CY2023	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	12800000	usd
CY2022	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	12800000	usd
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	3500000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	709600000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1044500000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	895700000	usd
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.55
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	9.74
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.72
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.54
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	9.70
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.67
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	108300000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	107200000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	102700000	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	108500000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	107600000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	103300000	shares
CY2023	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.45
CY2022	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.42
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.20
CY2021	us-gaap	Net Income Loss NetIncomeLoss	899200000	usd
CY2023	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	41400000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-225300000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-22400000	usd
CY2023	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	116900000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-674900000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-69000000.0	usd
CY2023	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	100000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	-1200000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	300000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	3700000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-1200000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-10200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-1900000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-2100000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-30200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	5500000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	6400000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesTax	400000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesTax	-0.0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesTax	-0.0	usd
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesNetOfTax	1200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesNetOfTax	0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesNetOfTax	0	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	148100000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-676700000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-76600000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	870500000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	380600000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	822600000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	3413500000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	899200000	usd
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	35000000.0	usd
CY2021	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	15700000	usd
CY2021	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	3500000	usd
CY2021	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	3500000	usd
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	124100000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-76600000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	4962600000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1057300000	usd
CY2022	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	39800000	usd
CY2022	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	18500000	usd
CY2022	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	157700000	usd
CY2022	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	12800000	usd
CY2022	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	153400000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-676700000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	5356000000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	722400000	usd
CY2023	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	34400000	usd
CY2023	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	11000000.0	usd
CY2023	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	12800000	usd
CY2023	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	158700000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	148100000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	6078400000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	722400000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1057300000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	899200000	usd
CY2023	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	62600000	usd
CY2022	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	68100000	usd
CY2021	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-21400000	usd
CY2023	us-gaap	Depreciation And Amortization DepreciationAndAmortization	63000000.0	usd
CY2022	us-gaap	Depreciation And Amortization DepreciationAndAmortization	52400000	usd
CY2021	us-gaap	Depreciation And Amortization DepreciationAndAmortization	33700000	usd
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	34300000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	39800000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	35100000	usd
CY2023	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-24900000	usd
CY2022	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-68600000	usd
CY2021	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	42000000.0	usd
CY2023	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	84000000.0	usd
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-21100000	usd
CY2021	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-39800000	usd
CY2023	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	64300000	usd
CY2022	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	63200000	usd
CY2021	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	49500000	usd
CY2023	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	23500000	usd
CY2022	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	22200000	usd
CY2021	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	16300000	usd
CY2023	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	84000000.0	usd
CY2022	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	73600000	usd
CY2021	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	66300000	usd
CY2023	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	42720900000	usd
CY2022	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	45407000000	usd
CY2021	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	59569600000	usd
CY2023	us-gaap	Proceeds From Sale And Collection Of Loans Heldforsale ProceedsFromSaleAndCollectionOfLoansHeldforsale	42168100000	usd
CY2022	us-gaap	Proceeds From Sale And Collection Of Loans Heldforsale ProceedsFromSaleAndCollectionOfLoansHeldforsale	47285000000	usd
CY2021	us-gaap	Proceeds From Sale And Collection Of Loans Heldforsale ProceedsFromSaleAndCollectionOfLoansHeldforsale	56647700000	usd
CY2023	wal	Capitalization Of Mortgage Servicing Rights Ms Rs CapitalizationOfMortgageServicingRightsMSRs	864500000	usd
CY2022	wal	Capitalization Of Mortgage Servicing Rights Ms Rs CapitalizationOfMortgageServicingRightsMSRs	719700000	usd
CY2021	wal	Capitalization Of Mortgage Servicing Rights Ms Rs CapitalizationOfMortgageServicingRightsMSRs	763800000	usd
CY2023	wal	Increase Decrease In Loans Held For Sale Mortgage Servicing Rights And Derivatives IncreaseDecreaseInLoansHeldForSaleMortgageServicingRightsAndDerivatives	-87800000	usd
CY2022	wal	Increase Decrease In Loans Held For Sale Mortgage Servicing Rights And Derivatives IncreaseDecreaseInLoansHeldForSaleMortgageServicingRightsAndDerivatives	73900000	usd
CY2021	wal	Increase Decrease In Loans Held For Sale Mortgage Servicing Rights And Derivatives IncreaseDecreaseInLoansHeldForSaleMortgageServicingRightsAndDerivatives	-177700000	usd
CY2023	wal	Assets Fair Value Adjustment Non Cash AssetsFairValueAdjustmentNonCash	122000000.0	usd
CY2022	wal	Assets Fair Value Adjustment Non Cash AssetsFairValueAdjustmentNonCash	22300000	usd
CY2021	wal	Assets Fair Value Adjustment Non Cash AssetsFairValueAdjustmentNonCash	1300000	usd
CY2023	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	-40800000	usd
CY2022	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	6800000	usd
CY2021	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	8400000	usd
CY2023	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	52700000	usd
CY2022	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	usd
CY2021	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-5900000	usd
CY2023	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-1100000	usd
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CY2021	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-15100000	usd
CY2023	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-114700000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	38700000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	157600000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-328600000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2245300000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-2654000000	usd
CY2023	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	15144700000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2396300000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	3248400000	usd
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	10036300000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	604200000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1634100000	usd
CY2023	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1532600000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	177000000.0	usd
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	164500000	usd
CY2023	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	201600000	usd
CY2022	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	281900000	usd
CY2021	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	595600000	usd
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	62100000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	100600000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	54900000	usd
CY2023	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	600000	usd
CY2022	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	36200000	usd
CY2021	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	36200000	usd
CY2023	wal	Proceeds From Redemptions Of Equity Securities Fvni ProceedsFromRedemptionsOfEquitySecuritiesFVNI	9000000.0	usd
CY2022	wal	Proceeds From Redemptions Of Equity Securities Fvni ProceedsFromRedemptionsOfEquitySecuritiesFVNI	6900000	usd
CY2021	wal	Proceeds From Redemptions Of Equity Securities Fvni ProceedsFromRedemptionsOfEquitySecuritiesFVNI	21000000.0	usd
CY2023	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	1500000	usd
CY2022	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	14100000	usd
CY2021	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	4400000	usd
CY2023	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	798200000	usd
CY2022	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	391900000	usd
CY2021	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	1182800000	usd
CY2023	wal	Purchase Of Other Investments PurchaseOfOtherInvestments	245100000	usd
CY2022	wal	Purchase Of Other Investments PurchaseOfOtherInvestments	346600000	usd
CY2021	wal	Purchase Of Other Investments PurchaseOfOtherInvestments	134600000	usd
CY2023	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	700000	usd
CY2022	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	usd
CY2021	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	usd
CY2023	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-1106800000	usd
CY2022	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	11172800000	usd
CY2021	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	12665000000	usd
CY2023	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	114300000	usd
CY2022	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	141000000.0	usd
CY2021	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	69400000	usd
CY2023	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	usd
CY2022	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	50000000.0	usd
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	1024400000	usd
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2159100000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-13130100000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-14711900000	usd
CY2023	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1688900000	usd
CY2022	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	6032100000	usd
CY2021	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	15681500000	usd
CY2023	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	9900000	usd
CY2022	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	578400000	usd
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1055700000	usd
CY2023	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	818100000	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	30700000	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	475900000	usd
CY2023	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	2341300000	usd
CY2022	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	4859000000	usd
CY2021	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	-1742100000	usd
CY2023	us-gaap	Proceeds From Short Term Debt Maturing In More Than Three Months ProceedsFromShortTermDebtMaturingInMoreThanThreeMonths	2661800000	usd
CY2022	us-gaap	Proceeds From Short Term Debt Maturing In More Than Three Months ProceedsFromShortTermDebtMaturingInMoreThanThreeMonths	0	usd
CY2021	us-gaap	Proceeds From Short Term Debt Maturing In More Than Three Months ProceedsFromShortTermDebtMaturingInMoreThanThreeMonths	0	usd
CY2023	us-gaap	Repayments Of Short Term Debt Maturing In More Than Three Months RepaymentsOfShortTermDebtMaturingInMoreThanThreeMonths	2681000000	usd
CY2022	us-gaap	Repayments Of Short Term Debt Maturing In More Than Three Months RepaymentsOfShortTermDebtMaturingInMoreThanThreeMonths	0	usd
CY2021	us-gaap	Repayments Of Short Term Debt Maturing In More Than Three Months RepaymentsOfShortTermDebtMaturingInMoreThanThreeMonths	0	usd
CY2023	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	11000000.0	usd
CY2022	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	18500000	usd
CY2021	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	15800000	usd
CY2023	us-gaap	Payments Of Dividends PaymentsOfDividends	171500000	usd
CY2022	us-gaap	Payments Of Dividends PaymentsOfDividends	166200000	usd
CY2021	us-gaap	Payments Of Dividends PaymentsOfDividends	127600000	usd
CY2023	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	100000	usd
CY2022	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	157700000	usd
CY2021	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	540300000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	3020400000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	11411800000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	15210600000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	532700000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	527000000.0	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2155300000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1043400000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	516400000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2671700000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1576100000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1043400000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	516400000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	1581000000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	452900000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	111600000	usd
CY2023	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	63600000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	197600000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	175700000	usd
CY2023	wal	Net Increase Decrease In Unfunded Commitments And Obligations NetIncreaseDecreaseInUnfundedCommitmentsAndObligations	77100000	usd
CY2022	wal	Net Increase Decrease In Unfunded Commitments And Obligations NetIncreaseDecreaseInUnfundedCommitmentsAndObligations	259300000	usd
CY2021	wal	Net Increase Decrease In Unfunded Commitments And Obligations NetIncreaseDecreaseInUnfundedCommitmentsAndObligations	294100000	usd
CY2023	wal	Transfers Of Securitized Lhfs To Afs Securities TransfersOfSecuritizedLHFSToAFSSecurities	276500000	usd
CY2022	wal	Transfers Of Securitized Lhfs To Afs Securities TransfersOfSecuritizedLHFSToAFSSecurities	205000000.0	usd
CY2021	wal	Transfers Of Securitized Lhfs To Afs Securities TransfersOfSecuritizedLHFSToAFSSecurities	144500000	usd
CY2023	wal	Ebo Loans Transfer From Held For Sale To Held In Portfolio EBOLoansTransferFromHeldForSaleToHeldInPortfolio	0	usd
CY2022	wal	Ebo Loans Transfer From Held For Sale To Held In Portfolio EBOLoansTransferFromHeldForSaleToHeldInPortfolio	1638100000	usd
CY2021	wal	Ebo Loans Transfer From Held For Sale To Held In Portfolio EBOLoansTransferFromHeldForSaleToHeldInPortfolio	0	usd
CY2023	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	6646800000	usd
CY2022	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	0	usd
CY2021	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	0	usd
CY2023	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	2357200000	usd
CY2022	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	780000000.0	usd
CY2021	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	usd
CY2023	wal	Transfers Of Mortgage Backed Securities In Settlement Of Secured Borrowings TransfersOfMortgageBackedSecuritiesInSettlementOfSecuredBorrowings	557300000	usd
CY2022	wal	Transfers Of Mortgage Backed Securities In Settlement Of Secured Borrowings TransfersOfMortgageBackedSecuritiesInSettlementOfSecuredBorrowings	610500000	usd
CY2021	wal	Transfers Of Mortgage Backed Securities In Settlement Of Secured Borrowings TransfersOfMortgageBackedSecuritiesInSettlementOfSecuredBorrowings	640600000	usd
CY2023	wal	Loan And Lease Transfer From Held In Portfolio To Held For Sale Operating Activity LoanAndLeaseTransferFromHeldInPortfolioToHeldForSaleOperatingActivity	531600000	usd
CY2023	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Use of estimates</span></div>The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Management's estimates and judgments are ongoing and are based on experience, current and expected future conditions, third-party evaluations and various other assumptions that management believes are reasonable under the circumstances. The results of these estimates form the basis for making judgments about the carrying values of assets and liabilities, as well as identifying and assessing the accounting treatment with respect to commitments and contingencies. Actual results may differ from those estimates and assumptions used in the Consolidated Financial Statements and related notes. Material estimates susceptible to significant changes in the near term, relate to: 1) the determination of the ACL; 2) certain assets and liabilities carried at fair value; 3) goodwill impairment and 4) accounting for income taxes.
CY2023	wal	Number Of Unconsolidated Subsidiaries NumberOfUnconsolidatedSubsidiaries	8	subsidiary
CY2023	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-top:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Reclassifications</span></div>Certain amounts in the Consolidated Income Statements for the prior periods have been reclassified to conform to the current presentation. The reclassifications had no effect on net income or stockholders’ equity as previously reported.
CY2023Q4	wal	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing Threshold For Evaluation FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruingThresholdForEvaluation	1000000	usd
CY2023Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	452000000	usd
CY2022Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	456000000	usd
CY2021Q3	us-gaap	Preferred Stock Dividend Rate Percentage PreferredStockDividendRatePercentage	0.04250
CY2021Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.0001
CY2021Q3	us-gaap	Preferred Stock Liquidation Preference PreferredStockLiquidationPreference	25
CY2021Q2	wal	Sale Of Stock Maximum Distribution Rate SaleOfStockMaximumDistributionRate	0.02
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	1429000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	1000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	179000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	1251000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	11849000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	18000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	702000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	11165000000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	1289000000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	0	usd
CY2022Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	177000000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	1112000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	7973000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	9000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	890000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	7092000000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	126000000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	160000000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-1300000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-22300000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	7000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	2449000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	695000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	4655000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	702000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	7104000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	319000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	4433000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	571000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	2467000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	890000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6900000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	708	positions
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	832	positions
CY2023	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossNotPreviouslyRecorded	18500000	usd
CY2023	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossWriteoff	17100000	usd
CY2022	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossNotPreviouslyRecorded	0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	5200000	usd
CY2023	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	2600000	usd
CY2023	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoff	0	usd
CY2023	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossRecovery	0	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	7800000	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	5200000	usd
CY2022	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	0	usd
CY2022	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoff	0	usd
CY2022	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossRecovery	0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	5200000	usd
CY2023Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	5000000	usd
CY2022Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	4000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	1429000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	11165000000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	126000000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	1289000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	7092000000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	160000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date Year One DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateYearOne	17000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	17000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year One Through Five DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive	20000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	20000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year5 Through10 DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear5Through10	86000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	76000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year10 DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10	1120000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	991000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Without Single Maturity Date DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityWithoutSingleMaturityDate	186000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	147000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	1429000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	1251000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	4099000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	4099000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	921000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	912000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	556000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	518000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	2094000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	2017000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	4179000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	3619000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	11849000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	11165000000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	4000000.0	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	7600000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	8400000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	44400000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	200000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	0	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-40400000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	7400000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	8400000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	0	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	100000	usd
CY2023	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	400000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	500000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	200000	usd
CY2023	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-400000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-500000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-100000	usd
CY2023	wal	Debt And Equity Securities Sold During Period Carrying Value DebtAndEquitySecuritiesSoldDuringPeriodCarryingValue	1600000000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-40400000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	7400000	usd
CY2023Q1	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	5900000000	usd
CY2023	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	4300000000	usd
CY2023Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	1402000000	usd
CY2022Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	1184000000	usd
CY2022	wal	Msr Capitalized Upon Sale Of Loan MSRCapitalizedUponSaleOfLoan	719700000	usd
CY2023	wal	Provision For And Change In Estimate Of Liability For Losses Under Representations And Warranties ProvisionForAndChangeInEstimateOfLiabilityForLossesUnderRepresentationsAndWarranties	-5200000	usd
CY2023	wal	Change In Fair Value Of Loans Held For Sale ChangeInFairValueOfLoansHeldForSale	15000000.0	usd
CY2022	wal	Change In Fair Value Of Loans Held For Sale ChangeInFairValueOfLoansHeldForSale	-6800000	usd
CY2023	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	18400000	usd
CY2022	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	5900000	usd
CY2023	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGain	55400000	usd
CY2022	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGain	408000000.0	usd
CY2023	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	136100000	usd
CY2022	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	40100000	usd
CY2023	wal	Loan Acquisition And Origination Fees LoanAcquisitionAndOriginationFees	57400000	usd
CY2022	wal	Loan Acquisition And Origination Fees LoanAcquisitionAndOriginationFees	63900000	usd
CY2023	wal	Net Gain On Loan Origination And Sale Activities NetGainOnLoanOriginationAndSaleActivities	193500000	usd
CY2022	wal	Net Gain On Loan Origination And Sale Activities NetGainOnLoanOriginationAndSaleActivities	104000000.0	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	50297000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	51862000000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	337000000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	310000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	49960000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	51552000000	usd
CY2023Q4	us-gaap	Financing Receivable Unamortized Loan Fee Cost FinancingReceivableUnamortizedLoanFeeCost	-108000000	usd
CY2022Q4	us-gaap	Financing Receivable Unamortized Loan Fee Cost FinancingReceivableUnamortizedLoanFeeCost	-141000000	usd
CY2023Q4	us-gaap	Financing Receivable Unamortized Purchase Premium Discount FinancingReceivableUnamortizedPurchasePremiumDiscount	177000000	usd
CY2022Q4	us-gaap	Financing Receivable Unamortized Purchase Premium Discount FinancingReceivableUnamortizedPurchasePremiumDiscount	195000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual No Allowance FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance	151000000	usd
CY2023Q4	wal	Financing Receivable Nonaccrual With Allowance FinancingReceivableNonaccrualWithAllowance	122000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual FinancingReceivableExcludingAccruedInterestNonaccrual	273000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruing	441000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruing	441000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual No Allowance FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance	20000000	usd
CY2022Q4	wal	Financing Receivable Nonaccrual With Allowance FinancingReceivableNonaccrualWithAllowance	65000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual FinancingReceivableExcludingAccruedInterestNonaccrual	85000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruing	582000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruing	582000000	usd
CY2023	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	12300000	usd
CY2022	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	4700000	usd
CY2021	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	5300000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	50297000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	51862000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	7504000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	12438000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	11558000000	usd
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CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	11829000000	usd
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CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff	2500000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff	4700000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff	18900000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff	7400000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff	300000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff	500000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Writeoff FinancingReceivableExcludingAccruedInterestRevolvingWriteoff	900000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	35200000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	15460000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	15098000000	usd
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CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	2319000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	1427000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2216000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	11345000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	51862000000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Modified Period FinancingReceivableExcludingAccruedInterestModifiedPeriod	206000000	usd
CY2023	us-gaap	Financing Receivable Modification To Total Financing Receivables Excluding Accrued Interest Percent FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent	0.004
CY2023Q4	wal	Financing Receivable Excluding Accrued Interest Modified Nonaccrual FinancingReceivableExcludingAccruedInterestModifiedNonaccrual	111000000	usd
CY2023Q4	wal	Financing Receivable Excluding Accrued Interest Modified Accrual Status FinancingReceivableExcludingAccruedInterestModifiedAccrualStatus	95000000	usd
CY2022Q4	wal	Financing Receivable Troubled Debt Restructured Loans Number Of Outstanding Contracts FinancingReceivableTroubledDebtRestructuredLoansNumberOfOutstandingContracts	7	securityloan
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Modified Accumulated FinancingReceivableExcludingAccruedInterestModifiedAccumulated	14000000	usd
CY2022Q4	wal	Reserves Allocated To Customers Whose Loan Terms Modified In Troubled Debt Restructurings ReservesAllocatedToCustomersWhoseLoanTermsModifiedInTroubledDebtRestructurings	4000000	usd
CY2022Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	0	usd
CY2022	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	3	securityloan
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Modified Period FinancingReceivableExcludingAccruedInterestModifiedPeriod	11000000	usd
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	securityloan
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	309700000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	56900000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	35200000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	5300000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	336700000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	252500000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	58700000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	9300000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	7800000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	309700000	usd
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CY2022	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	9400000	usd
CY2023Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	31600000	usd
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CY2023Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	49723000000	usd
CY2023Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	574000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	50297000000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	315100000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	21600000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	336700000	usd
CY2022Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	51526000000	usd
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CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	10700000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	309700000	usd
CY2023	wal	Loan And Lease Transfer From Held In Portfolio To Held For Sale Carrying Value LoanAndLeaseTransferFromHeldInPortfolioToHeldForSaleCarryingValue	6700000000	usd
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CY2022	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	780000000	usd
CY2022	us-gaap	Gain Loss On Sale Of Notes Receivable GainLossOnSaleOfNotesReceivable	-8400000	usd
CY2022Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	1148000000	usd
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CY2023	us-gaap	Servicing Asset At Fair Value Other Changes In Fair Value ServicingAssetAtFairValueOtherChangesInFairValue	-104000000	usd
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CY2022Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	1148000000	usd
CY2023Q4	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	68647000000	usd
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CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Favorable Interest Rate Change SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointFavorableInterestRateChange	62000000	usd
CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Discount Rate Increase SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointDiscountRateIncrease	21000000	usd
CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Discount Rate Decrease SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointDiscountRateDecrease	22000000	usd
CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of1 Percent Increase In Prepayment Speed SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf1PercentIncreaseInPrepaymentSpeed	32000000	usd
CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of1 Percent Decrease In Prepayment Speed SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf1PercentDecreaseInPrepaymentSpeed	35000000	usd
CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of10 Percent Increase Cost Of Service SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf10PercentIncreaseCostOfService	14000000	usd
CY2023Q4	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of10 Percent Decrease Cost Of Service SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf10PercentDecreaseCostOfService	14000000	usd
CY2023Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	96000000	usd
CY2022Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	95000000	usd
CY2023Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	82000000	usd
CY2022Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	60000000	usd
CY2023Q4	us-gaap	Furniture And Fixtures Gross FurnitureAndFixturesGross	108000000	usd
CY2022Q4	us-gaap	Furniture And Fixtures Gross FurnitureAndFixturesGross	97000000	usd
CY2023Q4	us-gaap	Land And Land Improvements LandAndLandImprovements	32000000	usd
CY2022Q4	us-gaap	Land And Land Improvements LandAndLandImprovements	32000000	usd
CY2023Q4	us-gaap	Leasehold Improvements Gross LeaseholdImprovementsGross	85000000	usd
CY2022Q4	us-gaap	Leasehold Improvements Gross LeaseholdImprovementsGross	66000000	usd
CY2023Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	142000000	usd
CY2022Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	83000000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	545000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	433000000	usd
CY2023Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	206000000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	157000000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	339000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	276000000	usd
CY2023	us-gaap	Depreciation Depreciation	49500000	usd
CY2022	us-gaap	Depreciation Depreciation	31800000	usd
CY2021	us-gaap	Depreciation Depreciation	20700000	usd
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	145000000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	163000000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	179000000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	185000000	usd
CY2023Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0296
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0281
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0214
CY2023Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y7M6D
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y4M24D
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y6M
CY2023Q4	us-gaap	Lessee Operating Lease Renewal Term LesseeOperatingLeaseRenewalTerm	P5Y
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	31000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	33000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	29000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	26000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	25000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	55000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	199000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	20000000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	179000000	usd
CY2023	us-gaap	Lease Cost LeaseCost	28800000	usd
CY2023	us-gaap	Variable Lease Cost VariableLeaseCost	4900000	usd
CY2022	us-gaap	Lease Cost LeaseCost	25400000	usd
CY2022	us-gaap	Variable Lease Cost VariableLeaseCost	4000000	usd
CY2021	us-gaap	Lease Cost LeaseCost	18800000	usd
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	3800000	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	19300000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	15100000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	16300000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	6300000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	51600000	usd
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	76700000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	527000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	527000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	178000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	36000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	142000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	178000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	25000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	153000000	usd
CY2023	us-gaap	Acquired Finite Lived Intangible Assets Weighted Average Useful Life AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife	P23Y8M12D
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	10500000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	10400000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6100000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	10000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	10000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	9000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	8000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	8000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	97000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	142000000	usd
CY2023Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	14520000000	usd
CY2022Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	19691000000	usd
CY2023Q4	us-gaap	Interest Bearing Domestic Deposit Demand InterestBearingDomesticDepositDemand	15916000000	usd
CY2022Q4	us-gaap	Interest Bearing Domestic Deposit Demand InterestBearingDomesticDepositDemand	9507000000	usd
CY2023Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	14791000000	usd
CY2022Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	19397000000	usd
CY2023Q4	wal	Time Deposits250000ormore TimeDeposits250000ormore	1478000000	usd
CY2022Q4	wal	Time Deposits250000ormore TimeDeposits250000ormore	1101000000	usd
CY2023Q4	wal	Time Deposits Lessthan250000 TimeDepositsLessthan250000	8628000000	usd
CY2022Q4	wal	Time Deposits Lessthan250000 TimeDepositsLessthan250000	3948000000	usd
CY2023Q4	us-gaap	Deposits Deposits	55333000000	usd
CY2022Q4	us-gaap	Deposits Deposits	53644000000	usd
CY2023Q4	wal	Time Deposits250000 Or More Retail Brokered TimeDeposits250000OrMoreRetailBrokered	5800000000	usd
CY2022Q4	wal	Time Deposits250000 Or More Retail Brokered TimeDeposits250000OrMoreRetailBrokered	2700000000	usd
CY2023Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	9092000000	usd
CY2023Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	1007000000	usd
CY2023Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	6000000	usd
CY2023Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	1000000	usd
CY2023Q4	us-gaap	Time Deposits TimeDeposits	10106000000	usd
CY2023Q4	us-gaap	Deposits Wholesale DepositsWholesale	6600000000	usd
CY2022Q4	us-gaap	Deposits Wholesale DepositsWholesale	4800000000	usd
CY2023Q4	wal	Reciprocal Deposits ReciprocalDeposits	13300000000	usd
CY2022Q4	wal	Reciprocal Deposits ReciprocalDeposits	2800000000	usd
CY2023Q4	wal	Deposits Earnings Credit DepositsEarningsCredit	17800000000	usd
CY2022Q4	wal	Deposits Earnings Credit DepositsEarningsCredit	12900000000	usd
CY2023	wal	Depositscostsdepositswithearningscredits Depositscostsdepositswithearningscredits	422500000	usd
CY2022	wal	Depositscostsdepositswithearningscredits Depositscostsdepositswithearningscredits	162800000	usd
CY2021	wal	Depositscostsdepositswithearningscredits Depositscostsdepositswithearningscredits	27400000	usd
CY2023Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	175000000	usd
CY2022Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	640000000	usd
CY2023Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	6200000000	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	4300000000	usd
CY2023Q4	us-gaap	Warehouse Agreement Borrowings WarehouseAgreementBorrowings	376000000	usd
CY2022Q4	us-gaap	Warehouse Agreement Borrowings WarehouseAgreementBorrowings	0	usd
CY2023Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	6000000	usd
CY2022Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	27000000	usd
CY2023Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	6784000000	usd
CY2022Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	4992000000	usd
CY2023Q4	us-gaap	Senior Notes SeniorNotes	0	usd
CY2022Q4	us-gaap	Senior Notes SeniorNotes	315000000	usd
CY2023Q4	us-gaap	Notes Payable NotesPayable	446000000	usd
CY2022Q4	us-gaap	Notes Payable NotesPayable	992000000	usd
CY2023Q4	us-gaap	Long Term Debt LongTermDebt	446000000	usd
CY2022Q4	us-gaap	Long Term Debt LongTermDebt	1307000000	usd
CY2023Q4	us-gaap	Other Borrowings OtherBorrowings	7230000000	usd
CY2022Q4	us-gaap	Other Borrowings OtherBorrowings	6299000000	usd
CY2023Q4	us-gaap	Federal Home Loan Bank Advances Weighted Average Interest Rate FederalHomeLoanBankAdvancesWeightedAverageInterestRate	0.0567
CY2022Q4	us-gaap	Federal Home Loan Bank Advances Weighted Average Interest Rate FederalHomeLoanBankAdvancesWeightedAverageInterestRate	0.0470
CY2023Q4	wal	Debt Instrument Classes Of Notes Number DebtInstrumentClassesOfNotesNumber	6	class
CY2023Q4	us-gaap	Subordinated Long Term Debt SubordinatedLongTermDebt	818000000	usd
CY2022Q4	us-gaap	Subordinated Long Term Debt SubordinatedLongTermDebt	817000000	usd
CY2023	wal	Numberof Statutory Business Trusts Formedor Acquired NumberofStatutoryBusinessTrustsFormedorAcquired	8	trust
CY2023Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	77000000	usd
CY2022Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	76000000	usd
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	14600000	shares
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Maximum Number Of Shares Per Employee ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesPerEmployee	300000	shares
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	4900000	shares
CY2023Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions	39000000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Remaining Contractual Terms ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms	P1Y9M18D
CY2023	us-gaap	Preferred Stock Dividend Rate Percentage PreferredStockDividendRatePercentage	0.04250
CY2023Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.0001
CY2023Q4	us-gaap	Preferred Stock Liquidation Preference PreferredStockLiquidationPreference	25
CY2022	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0.27
CY2023	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0.27
CY2021	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	3500000	usd
CY2023Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.36
CY2023Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.36
CY2023Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.36
CY2023Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.37
CY2022Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.35
CY2022Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.35
CY2022Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.36
CY2022Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.36
CY2023Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	67000000	usd
CY2023Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	67000000	usd
CY2022Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	17000000	usd
CY2022Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	17000000	usd
CY2021Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.25
CY2021Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.25
CY2021Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.35
CY2021Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.35
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	124100000	usd
CY2023	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	152452	shares
CY2023	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	72.27
CY2022	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	200745	shares
CY2022	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	92.21
CY2021	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	180607	shares
CY2021	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	86.63
CY2023Q4	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	3875000000	usd
CY2023Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	-6000000	usd
CY2022Q4	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	447000000	usd
CY2022Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	17000000	usd
CY2023Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	29857000000	usd
CY2023Q4	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Asset At Fair Value DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue	267000000	usd
CY2023Q4	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Liability At Fair Value DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue	67000000	usd
CY2022Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	19695000000	usd
CY2022Q4	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Asset At Fair Value DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue	33000000	usd
CY2022Q4	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Liability At Fair Value DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue	40000000	usd
CY2021Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	45173000000	usd
CY2021Q4	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Asset At Fair Value DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue	36000000	usd
CY2021Q4	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Liability At Fair Value DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue	45000000	usd
CY2023Q4	wal	Derivative Asset Subject To Master Netting Arrangement Collateral Obligation To Return Cash Offset Against Derivative Asset Net Of Adjustments DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments	-202000000	usd
CY2023Q4	wal	Derivative Asset Subject To Master Netting Arrangement Collateral Obligation To Return Cash Offset Against Derivative Asset Net Of Adjustments DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments	-202000000	usd
CY2022Q4	wal	Derivative Asset Subject To Master Netting Arrangement Collateral Obligation To Return Cash Offset Against Derivative Asset Net Of Adjustments DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments	-4000000	usd
CY2022Q4	wal	Derivative Asset Subject To Master Netting Arrangement Collateral Obligation To Return Cash Offset Against Derivative Asset Net Of Adjustments DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments	-4000000	usd
CY2021Q4	wal	Derivative Asset Subject To Master Netting Arrangement Collateral Obligation To Return Cash Offset Against Derivative Asset Net Of Adjustments DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments	-1000000	usd
CY2021Q4	wal	Derivative Asset Subject To Master Netting Arrangement Collateral Obligation To Return Cash Offset Against Derivative Asset Net Of Adjustments DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments	-1000000	usd
CY2021Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	28000000	usd
CY2021Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	28000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	260000000	usd
CY2023Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	67000000	usd
CY2023Q4	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	193000000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	36000000	usd
CY2022Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	17000000	usd
CY2022Q4	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	19000000	usd
CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	38000000	usd
CY2021Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	28000000	usd
CY2021Q4	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	10000000	usd
CY2023Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	-9000000	usd
CY2023Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	-9000000	usd
CY2022Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	1000000	usd
CY2022Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	1000000	usd
CY2021Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	6000000	usd
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$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal

2024 Q1 Form 10-K Financial Statement

#000121254524000092 Filed on February 28, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WAL WESTERN ALLIANCE BANCORPORATION Stock $wal

2024 Q1 Form 10-K Financial Statement

#000121254524000092 Filed on February 28, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal