$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal

$wal Overview Financials Valuation SEC Filings Company Website

2022 Q3 Form 10-Q Financial Statement

#000121254522000130 Filed on July 29, 2022

Income Statement

Concept	2022 Q3	2022 Q2	2022 Q1
Revenue	$739.4M	$579.6M	$484.5M
YoY Change	66.98%	45.45%	45.02%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$13.30M	$11.70M	$11.10M
YoY Change	25.47%	30.0%	85.0%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$137.3M	$54.60M	$35.00M
YoY Change	323.77%	95.0%	108.33%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$329.6M	$323.6M	$298.2M
YoY Change	8.99%	17.16%	27.22%
Income Tax	$65.60M	$63.40M	$58.10M
% Of Pretax Income	19.9%	19.59%	19.48%
Net Earnings	$264.0M	$260.2M	$240.1M
YoY Change	11.44%	16.26%	24.73%
Net Earnings / Revenue	35.7%	44.89%	49.56%
Basic Earnings Per Share	$2.43	$2.40	$2.23
Diluted Earnings Per Share	$2.447M	$2.39	$2.22
COMMON SHARES
Basic Shares Outstanding	108.3M shares	107.3M shares	106.0M shares
Diluted Shares Outstanding	107.9M shares	107.7M shares	106.6M shares

Balance Sheet

Concept	2022 Q3	2022 Q2	2022 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$1.610B	$1.886B	$2.602B
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	$368.0M	$210.0M	$196.3M
YoY Change	128.29%	39.81%	41.84%
Goodwill			$40.00M
YoY Change
Intangibles
YoY Change
Long-Term Investments	$165.0M	$170.0M	$165.0M
YoY Change	-7.3%	-12.37%	-14.51%
Other Assets	$302.0M	$223.0M	$68.00M
YoY Change	2645.45%	502.7%	36.0%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$69.17B	$66.06B	$60.58B
YoY Change	31.06%	34.62%	39.59%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$1.198B
YoY Change
Accrued Expenses	$149.0M	$151.0M	$155.0M
YoY Change	29.57%	48.04%	82.35%
Deferred Revenue
YoY Change
Short-Term Debt	$5.096B	$3.979B	$70.30M
YoY Change	1042.86%	6807.99%	1306.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$149.0M	$151.0M	$155.0M
YoY Change	29.57%	48.04%	82.35%
LONG-TERM LIABILITIES
Long-Term Debt	$7.208B	$2.122B	$1.656B
YoY Change	344.12%	24.97%	204.41%
Other Long-Term Liabilities	$1.198B	$1.132B	$1.524B
YoY Change	50.69%	-9.87%	137.38%
Total Long-Term Liabilities	$7.208B	$3.254B	$3.180B
YoY Change	198.1%	10.16%	168.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$149.0M	$151.0M	$155.0M
Total Long-Term Liabilities	$7.208B	$3.254B	$3.180B
Total Liabilities	$64.14B	$61.10B	$55.56B
YoY Change	32.91%	35.66%	40.02%
SHAREHOLDERS EQUITY
Retained Earnings	$3.413B	$3.191B	$2.973B
YoY Change	32.96%	34.83%	37.07%
Common Stock	$2.154B	$2.095B	$2.084B
YoY Change	27.02%	24.14%	29.57%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$105.0M	$104.0M	$104.1M
YoY Change	22.24%	23.52%	23.93%
Treasury Stock Shares	2.549M shares	2.538M shares	2.536M shares
Shareholders Equity	$5.021B	$4.959B	$5.012B
YoY Change
Total Liabilities & Shareholders Equity	$69.17B	$66.06B	$60.58B
YoY Change	31.06%	34.62%	39.59%

Cashflow Statement

Concept	2022 Q3	2022 Q2	2022 Q1
OPERATING ACTIVITIES
Net Income	$264.0M	$260.2M	$240.1M
YoY Change	11.44%	16.26%	24.73%
Depreciation, Depletion And Amortization	$13.30M	$11.70M	$11.10M
YoY Change	25.47%	30.0%	85.0%
Cash From Operating Activities	$490.9M	$337.1M	-$622.9M
YoY Change	-137.54%	-116.35%	-722.28%
INVESTING ACTIVITIES
Capital Expenditures	-$36.80M	-$21.20M	-$26.20M
YoY Change	102.2%	562.5%	151.92%
Acquisitions			$50.00M
YoY Change
Other Investing Activities	-$3.891B	-$7.074B	-$2.571B
YoY Change	-26.11%	435.2%	-36.49%
Cash From Investing Activities	-$3.928B	-$7.096B	$2.598B
YoY Change	-25.67%	435.51%	-164.0%
FINANCING ACTIVITIES
Cash Dividend Paid			$40.50M
YoY Change			60.08%
Common Stock Issuance & Retirement, Net			$94.90M
YoY Change			-145.36%
Debt Paid & Issued, Net			$9.500M
YoY Change
Cash From Financing Activities	3.161B	6.042B	$4.061B
YoY Change	-23.17%	320.86%	-38.79%
NET CHANGE
Cash From Operating Activities	490.9M	337.1M	-$622.9M
Cash From Investing Activities	-3.928B	-7.096B	$2.598B
Cash From Financing Activities	3.161B	6.042B	$4.061B
Net Change In Cash	-276.3M	-716.5M	$6.035B
YoY Change	-88.85%	-63.27%	125.64%
FREE CASH FLOW
Cash From Operating Activities	$490.9M	$337.1M	-$622.9M
Capital Expenditures	-$36.80M	-$21.20M	-$26.20M
Free Cash Flow	$527.7M	$358.3M	-$596.7M
YoY Change	-140.92%	-117.41%	-640.0%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2022-06-30
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	dei	Entity File Number EntityFileNumber	001-32550
	dei	Entity Registrant Name EntityRegistrantName	WESTERN ALLIANCE BANCORPORATION
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	88-0365922
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	dei	Entity Address State Or Province EntityAddressStateOrProvince	AZ
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	wal	Loan Servicing Fees Net LoanServicingFeesNet	-20800000	usd
CY2022Q2	wal	Net Gain On Loan Origination And Sale Activities NetGainOnLoanOriginationAndSaleActivities	27200000	usd
CY2021Q2	wal	Net Gain On Loan Origination And Sale Activities NetGainOnLoanOriginationAndSaleActivities	132000000.0	usd
	wal	Net Gain On Loan Origination And Sale Activities NetGainOnLoanOriginationAndSaleActivities	64100000	usd
	wal	Net Gain On Loan Origination And Sale Activities NetGainOnLoanOriginationAndSaleActivities	132000000.0	usd
CY2022Q2	wal	Gain On Recovery From Credit Guarantees GainOnRecoveryFromCreditGuarantees	9000000.0	usd
CY2021Q2	wal	Gain On Recovery From Credit Guarantees GainOnRecoveryFromCreditGuarantees	0	usd
	wal	Gain On Recovery From Credit Guarantees GainOnRecoveryFromCreditGuarantees	11300000	usd
	wal	Gain On Recovery From Credit Guarantees GainOnRecoveryFromCreditGuarantees	0	usd
CY2022Q2	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	7600000	usd
CY2021Q2	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	7400000	usd
	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	14600000	usd
	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	14100000	usd
CY2022Q2	wal	Commercial Banking Related Income CommercialBankingRelatedIncome	5800000	usd
CY2021Q2	wal	Commercial Banking Related Income CommercialBankingRelatedIncome	4500000	usd
	wal	Commercial Banking Related Income CommercialBankingRelatedIncome	10900000	usd
	wal	Commercial Banking Related Income CommercialBankingRelatedIncome	7900000	usd
CY2022Q2	wal	Incomefrom Equity Investments IncomefromEquityInvestments	5200000	usd
CY2021Q2	wal	Incomefrom Equity Investments IncomefromEquityInvestments	6800000	usd
	wal	Incomefrom Equity Investments IncomefromEquityInvestments	9300000	usd
	wal	Incomefrom Equity Investments IncomefromEquityInvestments	14400000	usd
CY2022Q2	wal	Gain On Sales Of Investment Securities GainOnSalesOfInvestmentSecurities	200000	usd
CY2021Q2	wal	Gain On Sales Of Investment Securities GainOnSalesOfInvestmentSecurities	0	usd
	wal	Gain On Sales Of Investment Securities GainOnSalesOfInvestmentSecurities	6700000	usd
	wal	Gain On Sales Of Investment Securities GainOnSalesOfInvestmentSecurities	100000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-10000000.0	usd
CY2021Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	3200000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-16600000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	1700000	usd
CY2022Q2	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	5000000.0	usd
CY2021Q2	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	2900000	usd
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	14500000	usd
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	6300000	usd
CY2022Q2	us-gaap	Noninterest Income NoninterestIncome	95000000.0	usd
CY2021Q2	us-gaap	Noninterest Income NoninterestIncome	136000000.0	usd
	us-gaap	Noninterest Income NoninterestIncome	201300000	usd
	us-gaap	Noninterest Income NoninterestIncome	155700000	usd
CY2022Q2	us-gaap	Labor And Related Expense LaborAndRelatedExpense	139000000.0	usd
CY2021Q2	us-gaap	Labor And Related Expense LaborAndRelatedExpense	128900000	usd
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	277300000	usd
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	212600000	usd
CY2022Q2	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	25100000	usd
CY2021Q2	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	14000000.0	usd
	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	49100000	usd
	wal	Legal Professional And Director Fees LegalProfessionalAndDirectorFees	24100000	usd
CY2022Q2	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	19700000	usd
CY2021Q2	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	15000000.0	usd
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	37300000	usd
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	24900000	usd
CY2022Q2	wal	Non Interest Expense Deposit Costs NonInterestExpenseDepositCosts	18100000	usd
CY2021Q2	wal	Non Interest Expense Deposit Costs NonInterestExpenseDepositCosts	7100000	usd
	wal	Non Interest Expense Deposit Costs NonInterestExpenseDepositCosts	27400000	usd
	wal	Non Interest Expense Deposit Costs NonInterestExpenseDepositCosts	13400000	usd
CY2022Q2	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	14700000	usd
CY2021Q2	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	22300000	usd
	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	25500000	usd
	us-gaap	Expense Related To Distribution Or Servicing And Underwriting Fees ExpenseRelatedToDistributionOrServicingAndUnderwritingFees	22300000	usd
CY2022Q2	us-gaap	Occupancy Net OccupancyNet	13000000.0	usd
CY2021Q2	us-gaap	Occupancy Net OccupancyNet	10400000	usd
	us-gaap	Occupancy Net OccupancyNet	25800000	usd
	us-gaap	Occupancy Net OccupancyNet	19000000.0	usd
CY2022Q2	us-gaap	General Insurance Expense GeneralInsuranceExpense	6900000	usd
CY2021Q2	us-gaap	General Insurance Expense GeneralInsuranceExpense	5500000	usd
	us-gaap	General Insurance Expense GeneralInsuranceExpense	14100000	usd
	us-gaap	General Insurance Expense GeneralInsuranceExpense	9700000	usd
CY2022Q2	us-gaap	Loan Processing Fee LoanProcessingFee	6400000	usd
CY2021Q2	us-gaap	Loan Processing Fee LoanProcessingFee	10500000	usd
	us-gaap	Loan Processing Fee LoanProcessingFee	12900000	usd
	us-gaap	Loan Processing Fee LoanProcessingFee	10500000	usd
CY2022Q2	us-gaap	Business Development BusinessDevelopment	5400000	usd
CY2021Q2	us-gaap	Business Development BusinessDevelopment	3200000	usd
	us-gaap	Business Development BusinessDevelopment	9800000	usd
	us-gaap	Business Development BusinessDevelopment	4600000	usd
CY2022Q2	wal	Net Loss Gain On Sales Valuations Of Repossessed Assets And Bank Premises Net NetLossGainOnSalesValuationsOfRepossessedAssetsAndBankPremisesNet	-300000	usd
CY2021Q2	wal	Net Loss Gain On Sales Valuations Of Repossessed Assets And Bank Premises Net NetLossGainOnSalesValuationsOfRepossessedAssetsAndBankPremisesNet	-1500000	usd
	wal	Net Loss Gain On Sales Valuations Of Repossessed Assets And Bank Premises Net NetLossGainOnSalesValuationsOfRepossessedAssetsAndBankPremisesNet	-200000	usd
	wal	Net Loss Gain On Sales Valuations Of Repossessed Assets And Bank Premises Net NetLossGainOnSalesValuationsOfRepossessedAssetsAndBankPremisesNet	-1800000	usd
CY2022Q2	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	0	usd
CY2021Q2	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	15700000	usd
	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	400000	usd
	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	16100000	usd
CY2022Q2	us-gaap	Other Noninterest Expense OtherNoninterestExpense	20900000	usd
CY2021Q2	us-gaap	Other Noninterest Expense OtherNoninterestExpense	13700000	usd
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	38100000	usd
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	24400000	usd
CY2022Q2	us-gaap	Noninterest Expense NoninterestExpense	268900000	usd
CY2021Q2	us-gaap	Noninterest Expense NoninterestExpense	244800000	usd
	us-gaap	Noninterest Expense NoninterestExpense	517500000	usd
	us-gaap	Noninterest Expense NoninterestExpense	379800000	usd
CY2022Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	323600000	usd
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	276200000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	621800000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	510600000	usd
CY2022Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	63400000	usd
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	52400000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	121500000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	94300000	usd
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	260200000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	223800000	usd
	us-gaap	Net Income Loss NetIncomeLoss	500300000	usd
	us-gaap	Net Income Loss NetIncomeLoss	416300000	usd
CY2022Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	3200000	usd
CY2021Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	usd
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	6400000	usd
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	usd
CY2022Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	257000000.0	usd
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	223800000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	493900000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	416300000	usd
CY2022Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.40
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.18
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.63
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.09
CY2022Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.39
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.17
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.61
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.07
CY2022Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	107300000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	102700000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	106700000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	101800000	shares
CY2022Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	107700000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	103400000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	107100000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	102400000	shares
CY2022Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.35
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.25
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.70
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.50
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	260200000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	223800000	usd
	us-gaap	Net Income Loss NetIncomeLoss	500300000	usd
	us-gaap	Net Income Loss NetIncomeLoss	416300000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-93300000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	14600000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-174100000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-8900000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-284500000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	44800000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-532400000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-27200000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	-700000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	-0.0	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	-1400000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	-100000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-2000000.0	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-200000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	4200000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-500000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-100000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0.0	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-1900000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0.0	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	300000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	0	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	5400000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	100000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-282800000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44600000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-533600000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-27800000	usd
CY2022Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-22600000	usd
CY2021Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	268400000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-33300000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	388500000	usd
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	3712700000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	223800000	usd
CY2021Q2	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	9600000	usd
CY2021Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	200000	usd
CY2021Q2	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	69800000	usd
CY2021Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	25800000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44600000	usd
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	4034500000	usd
CY2022Q1	us-gaap	Stockholders Equity StockholdersEquity	5011600000	usd
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	260200000	usd
CY2022Q2	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	11100000	usd
CY2022Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	200000	usd
CY2022Q2	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	3200000	usd
CY2022Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	37900000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-282800000	usd
CY2022Q2	us-gaap	Stockholders Equity StockholdersEquity	4958800000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	3413500000	usd
	us-gaap	Net Income Loss NetIncomeLoss	416300000	usd
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	17700000	usd
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	13100000	usd
	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	279000000.0	usd
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	51100000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-27800000	usd
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	4034500000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	4962600000	usd
	us-gaap	Net Income Loss NetIncomeLoss	500300000	usd
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	20900000	usd
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	17500000	usd
	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	107700000	usd
	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	6400000	usd
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	75200000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-533600000	usd
CY2022Q2	us-gaap	Stockholders Equity StockholdersEquity	4958800000	usd
	us-gaap	Net Income Loss NetIncomeLoss	500300000	usd
	us-gaap	Net Income Loss NetIncomeLoss	416300000	usd
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	36500000	usd
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	46900000	usd
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	22800000	usd
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	15000000.0	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	20900000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	17500000	usd
	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-10900000	usd
	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	10300000	usd
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-12300000	usd
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-21400000	usd
	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	28800000	usd
	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	23700000	usd
	us-gaap	Operating Lease Expense OperatingLeaseExpense	10800000	usd
	us-gaap	Operating Lease Expense OperatingLeaseExpense	6700000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	30500000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	38700000	usd
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	25371000000	usd
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	21841100000	usd
	us-gaap	Proceeds From Sale And Collection Of Loans Heldforsale ProceedsFromSaleAndCollectionOfLoansHeldforsale	26301500000	usd
	us-gaap	Proceeds From Sale And Collection Of Loans Heldforsale ProceedsFromSaleAndCollectionOfLoansHeldforsale	20582600000	usd
	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	397500000	usd
	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	282300000	usd
	us-gaap	Servicing Asset At Fair Value Period Increase Decrease ServicingAssetAtFairValuePeriodIncreaseDecrease	109800000	usd
	us-gaap	Servicing Asset At Fair Value Period Increase Decrease ServicingAssetAtFairValuePeriodIncreaseDecrease	-20300000	usd
	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-4900000	usd
	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-1500000	usd
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	59100000	usd
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	29800000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-960000000.0	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-1123500000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2235400000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2927200000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	410500000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	963300000	usd
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	119600000	usd
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	usd
	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	129500000	usd
	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	50600000	usd
	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	363800000	usd
	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	406400000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	18900000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	4400000	usd
	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	34900000	usd
	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	28400000	usd
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	300000	usd
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	2400000	usd
	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	14100000	usd
	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	600000	usd
	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	777600000	usd
	wal	Purchase Of Other Investments PurchaseOfOtherInvestments	168600000	usd
	wal	Purchase Of Other Investments PurchaseOfOtherInvestments	57100000	usd
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	7954500000	usd
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	3523800000	usd
	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	47400000	usd
	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	13600000	usd
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	50000000.0	usd
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	1013400000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	9693100000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-6221600000	usd
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	6100100000	usd
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	9990500000	usd
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	486600000	usd
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	831400000	usd
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	17400000	usd
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	usd
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	3524600000	usd
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-2967700000	usd
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	17500000	usd
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	12900000	usd
	us-gaap	Payments Of Dividends PaymentsOfDividends	81600000	usd
	us-gaap	Payments Of Dividends PaymentsOfDividends	51100000	usd
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	107700000	usd
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	279000000.0	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	10102500000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	8069200000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	1369400000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	724100000	usd
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	516400000	usd
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2671700000	usd
CY2022Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1885800000	usd
CY2021Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	3395800000	usd
	us-gaap	Interest Paid Net InterestPaidNet	87900000	usd
	us-gaap	Interest Paid Net InterestPaidNet	94400000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	185000000.0	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	111100000	usd
	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	1505700000	usd
	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	usd
	wal	Transfers Of Mortgage Backed Securities In Settlement Of Secured Borrowings TransfersOfMortgageBackedSecuritiesInSettlementOfSecuredBorrowings	281500000	usd
	wal	Transfers Of Mortgage Backed Securities In Settlement Of Secured Borrowings TransfersOfMortgageBackedSecuritiesInSettlementOfSecuredBorrowings	312800000	usd
	wal	Net Increase Decrease In Unfunded Commitments And Obligations NetIncreaseDecreaseInUnfundedCommitmentsAndObligations	207200000	usd
	wal	Net Increase Decrease In Unfunded Commitments And Obligations NetIncreaseDecreaseInUnfundedCommitmentsAndObligations	118700000	usd
	wal	Net Increase In Unsettled Loans Hfi And Investment Securities Purchased NetIncreaseInUnsettledLoansHFIAndInvestmentSecuritiesPurchased	22700000	usd
	wal	Net Increase In Unsettled Loans Hfi And Investment Securities Purchased NetIncreaseInUnsettledLoansHFIAndInvestmentSecuritiesPurchased	618400000	usd
	wal	Transfers Of Securitized Lhfs To Afs Securities TransfersOfSecuritizedLHFSToAFSSecurities	89600000	usd
	wal	Transfers Of Securitized Lhfs To Afs Securities TransfersOfSecuritizedLHFSToAFSSecurities	0	usd
	wal	Number Of Wholly Owned Subsidiaries Non Bank Subsidiaries NumberOfWhollyOwnedSubsidiariesNonBankSubsidiaries	2	subsidiary
	us-gaap	Use Of Estimates UseOfEstimates	Use of estimatesThe 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 that are susceptible to significant changes in the near term, particularly to the extent that economic conditions worsen or persist longer than expected in an adverse state, relate to: 1) the determination of the allowance for credit losses; 2) certain assets and liabilities carried at fair value; and 3) accounting for income taxes.
	wal	Number Of Unconsolidated Subsidiaries NumberOfUnconsolidatedSubsidiaries	8	subsidiary
	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	ReclassificationsCertain amounts in the Consolidated Income Statements for the prior periods have been reclassified to conform to the current presentation. The reclassifications have no effect on net income or stockholders’ equity as previously reported.
CY2022Q1	us-gaap	Business Acquisition Effective Date Of Acquisition1 BusinessAcquisitionEffectiveDateOfAcquisition1	2022-01-25
	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	67800000	usd
CY2022Q1	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	1200000000	usd
CY2022Q1	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	17200000	usd
	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	400000	usd
CY2022Q2	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	0	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents	600000	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangibles BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles	27500000	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Other Noncurrent Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets	100000	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets	28200000	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Noncurrent Liabilities Other BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther	400000	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	400000	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet	27800000	usd
	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	50600000	usd
CY2022Q1	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	17200000	usd
	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	67800000	usd
CY2022Q1	us-gaap	Goodwill Goodwill	40000000.0	usd
CY2022Q1	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangibles BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles	27500000	usd
CY2022Q1	us-gaap	Goodwill Goodwill	40000000	usd
CY2021Q2	us-gaap	Business Acquisition Effective Date Of Acquisition1 BusinessAcquisitionEffectiveDateOfAcquisition1	2021-04-07
CY2021Q2	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	15700000	usd
	wal	Acquisition And Restructure Expenses AcquisitionAndRestructureExpenses	16100000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents	207200000	usd
CY2021Q2	wal	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Loans Held For Sale BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLoansHeldForSale	3552900000	usd
CY2021Q2	wal	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Servicing Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedServicingAssets	1347000000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Property Plant And Equipment BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment	11300000	usd
CY2021Q2	wal	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Operating Right Of Use Asset BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingRightOfUseAsset	18900000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangibles BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles	141000000.0	usd
CY2021Q2	wal	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Loans Eligible For Repurchase BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLoansEligibleForRepurchase	2744700000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deferred Tax Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets	6600000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Other Noncurrent Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets	236000000.0	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets	8265600000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Noncurrent Liabilities Long Term Debt BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt	3633900000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Capital Lease Obligation BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation	18900000	usd
CY2021Q2	wal	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liability For Loans Eligible For Repurchase BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilityForLoansEligibleForRepurchase	2744700000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Noncurrent Liabilities Other BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther	149500000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	6547000000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet	1718600000	usd
	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	1231600000	usd
CY2021Q2	wal	Business Combination Elimination Of Pre Existing Debt And Other BusinessCombinationEliminationOfPreExistingDebtAndOther	686800000	usd
	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	1918400000	usd
CY2021Q2	us-gaap	Goodwill Goodwill	199800000	usd
CY2021Q2	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangibles BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles	141000000	usd
CY2021Q2	us-gaap	Goodwill Goodwill	199800000	usd
CY2021Q2	us-gaap	Business Acquisition Purchase Price Allocation Goodwill Expected Tax Deductible Amount BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount	185000000	usd
CY2021Q2	wal	Business Acquisition Pro Forma Interest Income BusinessAcquisitionProFormaInterestIncome	400500000	usd
	wal	Business Acquisition Pro Forma Interest Income BusinessAcquisitionProFormaInterestIncome	753800000	usd
CY2021Q2	wal	Business Acquisition Pro Forma Non Interest Income BusinessAcquisitionProFormaNonInterestIncome	132400000	usd
	wal	Business Acquisition Pro Forma Non Interest Income BusinessAcquisitionProFormaNonInterestIncome	222000000.0	usd
CY2021Q2	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	243800000	usd
	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	424000000.0	usd
CY2022Q2	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	1218000000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	4000000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	100000000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	1122000000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	7960000000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	9000000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	701000000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	7268000000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	178000000	usd
CY2022Q2	wal	Equitysecurities Fvni Accumulated Gross Unrealized Gain Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2022Q2	wal	Equitysecurities Fvni Accumulated Gross Unrealized Loss Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedLossBeforeTax	8000000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	170000000	usd
CY2021Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	1107000000	usd
CY2021Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	43000000	usd
CY2021Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	4000000	usd
CY2021Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	1146000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6167000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	103000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	81000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	6189000000	usd
CY2021Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	152000000	usd
CY2021Q4	wal	Equitysecurities Fvni Accumulated Gross Unrealized Gain Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedGainBeforeTax	8000000	usd
CY2021Q4	wal	Equitysecurities Fvni Accumulated Gross Unrealized Loss Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedLossBeforeTax	1000000	usd
CY2021Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	159000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	483000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	5848000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	218000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1219000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	701000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	7067000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	68000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	3046000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	13000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	170000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	81000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	3216000000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	785	positions
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	179	positions
CY2022Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	3000000	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	0	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoff	0	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossRecovery	0	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	3000000	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	5000000	usd
	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	2000000	usd
	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoff	0	usd
	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossRecovery	0	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	3000000	usd
CY2021Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	9000000	usd
CY2021Q2	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	-3000000	usd
CY2021Q2	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoff	0	usd
CY2021Q2	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossRecovery	0	usd
CY2021Q2	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	6000000	usd
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	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	-1000000	usd
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	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	6900000	usd
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	wal	Msr Capitalized Upon Sale Of Loan MSRCapitalizedUponSaleOfLoan	397500000	usd
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	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	698600000	usd
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CY2022Q2	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	273200000	usd
CY2021Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	38812000000	usd
CY2021Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	263000000	usd
CY2021Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	39075000000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	236400000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	16100000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	252500000	usd
CY2022Q1	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	950000000	usd
CY2021Q2	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	0	usd
CY2021Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	698000000	usd
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CY2022Q2	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	194000000	usd
CY2021Q2	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	282000000	usd
	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	398000000	usd
CY2022Q2	us-gaap	Servicing Asset At Fair Value Disposals ServicingAssetAtFairValueDisposals	350000000	usd
CY2021Q2	us-gaap	Servicing Asset At Fair Value Disposals ServicingAssetAtFairValueDisposals	872000000	usd
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	us-gaap	Servicing Asset At Fair Value Disposals ServicingAssetAtFairValueDisposals	350000000	usd
CY2022Q2	us-gaap	Servicing Asset At Fair Value Changes In Fair Value Resulting From Changes In Valuation Inputs Or Changes In Assumptions ServicingAssetAtFairValueChangesInFairValueResultingFromChangesInValuationInputsOrChangesInAssumptions	62000000	usd
CY2021Q2	us-gaap	Servicing Asset At Fair Value Changes In Fair Value Resulting From Changes In Valuation Inputs Or Changes In Assumptions ServicingAssetAtFairValueChangesInFairValueResultingFromChangesInValuationInputsOrChangesInAssumptions	7000000	usd
	us-gaap	Servicing Asset At Fair Value Changes In Fair Value Resulting From Changes In Valuation Inputs Or Changes In Assumptions ServicingAssetAtFairValueChangesInFairValueResultingFromChangesInValuationInputsOrChangesInAssumptions	143000000	usd
CY2022Q2	us-gaap	Servicing Asset At Fair Value Other Changes In Fair Value ServicingAssetAtFairValueOtherChangesInFairValue	-30000000	usd
CY2021Q2	us-gaap	Servicing Asset At Fair Value Other Changes In Fair Value ServicingAssetAtFairValueOtherChangesInFairValue	-67000000	usd
	us-gaap	Servicing Asset At Fair Value Other Changes In Fair Value ServicingAssetAtFairValueOtherChangesInFairValue	-63000000	usd
CY2022Q2	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	826000000	usd
CY2021Q2	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	726000000	usd
CY2022Q2	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	826000000	usd
CY2022Q2	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	52184000000	usd
CY2021Q2	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	57089000000	usd
	wal	Msr Sales Upb Of Underlying Loans MSRSalesUPBOfUnderlyingLoans	24100000000	usd
CY2022Q2	wal	Msr Sales Upb Of Underlying Loans MSRSalesUPBOfUnderlyingLoans	24100000000	usd
CY2021Q2	wal	Msr Sales Upb Of Underlying Loans MSRSalesUPBOfUnderlyingLoans	65300000000	usd
CY2022Q2	wal	Msr Loan Sales Receivable MSRLoanSalesReceivable	68000000	usd
CY2022Q2	us-gaap	Contractually Specified Servicing Fees Late Fees And Ancillary Fees Earned In Exchange For Servicing Financial Assets ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets	48900000	usd
CY2021Q2	us-gaap	Contractually Specified Servicing Fees Late Fees And Ancillary Fees Earned In Exchange For Servicing Financial Assets ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets	61000000	usd
CY2022Q2	wal	Servicing Advances Net ServicingAdvancesNet	-68000000	usd
CY2021Q4	wal	Servicing Advances Net ServicingAdvancesNet	-82000000	usd
CY2022Q2	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	826000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Adverse Interest Rate Change SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointAdverseInterestRateChange	-35000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Favorable Interest Rate Change SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointFavorableInterestRateChange	27000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Discount Rate Increase SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointDiscountRateIncrease	16000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of50 Basis Point Discount Rate Decrease SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf50BasisPointDiscountRateDecrease	17000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of1 Percent Increase In Prepayment Speed SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf1PercentIncreaseInPrepaymentSpeed	23000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of1 Percent Decrease In Prepayment Speed SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf1PercentDecreaseInPrepaymentSpeed	25000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of10 Percent Increase Cost Of Service SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf10PercentIncreaseCostOfService	10000000	usd
CY2022Q2	wal	Sensitivity Analysis Of Fair Value Transferors Interests In Transferred Financial Assets Impact Of10 Percent Decrease Cost Of Service SensitivityAnalysisOfFairValueTransferorsInterestsInTransferredFinancialAssetsImpactOf10PercentDecreaseCostOfService	10000000	usd
CY2022Q2	us-gaap	Federal Funds Purchased FederalFundsPurchased	1860000000	usd
CY2021Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	675000000	usd
CY2022Q2	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	2000000000	usd
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	0	usd
CY2022Q2	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	79000000	usd
CY2021Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	17000000	usd
CY2022Q2	us-gaap	Other Short Term Borrowings OtherShortTermBorrowings	40000000	usd
CY2021Q4	us-gaap	Other Short Term Borrowings OtherShortTermBorrowings	35000000	usd
CY2022Q2	us-gaap	Short Term Borrowings ShortTermBorrowings	3979000000	usd
CY2021Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	727000000	usd
CY2022Q2	us-gaap	Senior Notes SeniorNotes	316000000	usd
CY2021Q4	us-gaap	Senior Notes SeniorNotes	318000000	usd
CY2022Q2	us-gaap	Notes Payable NotesPayable	915000000	usd
CY2021Q4	us-gaap	Notes Payable NotesPayable	457000000	usd
CY2022Q2	us-gaap	Long Term Debt LongTermDebt	1231000000	usd
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	775000000	usd
CY2022Q2	us-gaap	Other Borrowings OtherBorrowings	5210000000	usd
CY2021Q4	us-gaap	Other Borrowings OtherBorrowings	1502000000	usd
CY2022Q2	us-gaap	Subordinated Long Term Debt SubordinatedLongTermDebt	816000000	usd
CY2021Q4	us-gaap	Subordinated Long Term Debt SubordinatedLongTermDebt	815000000	usd
CY2021Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	81000000	usd
CY2022Q2	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0.27
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CY2022Q2	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	86.78
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	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	2300000	shares
CY2021Q2	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	91.00
CY2022Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.35
CY2021Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.25
CY2022Q2	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	2635	shares
	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	188169	shares
CY2022Q2	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	77.50
	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	93.29
	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	156419	shares
CY2021Q2	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	106.23
	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	83.89
CY2022Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-235100000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-282500000	usd
CY2022Q2	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	300000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-282800000	usd
CY2022Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-517900000	usd
CY2021Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	19900000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	44600000	usd
CY2021Q2	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	0	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44600000	usd
CY2021Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	64500000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	15700000	usd
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CY2022Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-517900000	usd
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CY2021Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	64500000	usd
CY2022Q2	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	494000000	usd
CY2022Q2	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	6000000	usd
CY2021Q4	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	1391000000	usd
CY2021Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	39000000	usd
CY2022Q2	us-gaap	Derivative Asset Collateral Obligation To Return Cash Offset DerivativeAssetCollateralObligationToReturnCashOffset	9000000	usd
CY2022Q2	us-gaap	Derivative Asset Collateral Obligation To Return Cash Offset DerivativeAssetCollateralObligationToReturnCashOffset	9000000	usd
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CY2021Q4	us-gaap	Derivative Asset Collateral Obligation To Return Cash Offset DerivativeAssetCollateralObligationToReturnCashOffset	1000000	usd
CY2022Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-55000000	usd
CY2022Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-55000000	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
CY2021Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-31000000	usd
CY2021Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-31000000	usd
CY2022Q2	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	60000000	usd
CY2022Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-55000000	usd
CY2022Q2	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	5000000	usd
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CY2021Q4	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	10000000	usd
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CY2021Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-31000000	usd
CY2021Q2	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	9000000	usd
CY2022Q2	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	24000000	usd
CY2022Q2	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	24000000	usd
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CY2021Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	6000000	usd
CY2022Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	55000000	usd
CY2022Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	55000000	usd
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CY2021Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	28000000	usd
CY2021Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	31000000	usd
CY2021Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	31000000	usd
CY2022Q2	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	79000000	usd
CY2022Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	55000000	usd
CY2022Q2	us-gaap	Derivative Liability After Offset Subject To Master Netting Arrangement DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement	24000000	usd
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CY2021Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	28000000	usd
CY2021Q4	us-gaap	Derivative Liability After Offset Subject To Master Netting Arrangement DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement	68000000	usd
CY2021Q2	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	102000000	usd
CY2021Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	31000000	usd
CY2021Q2	us-gaap	Derivative Liability After Offset Subject To Master Netting Arrangement DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement	71000000	usd
CY2022Q2	us-gaap	Derivative Asset Not Subject To Master Netting Arrangement DerivativeAssetNotSubjectToMasterNettingArrangement	19000000	usd
CY2022Q2	us-gaap	Derivative Asset Not Subject To Master Netting Arrangement DerivativeAssetNotSubjectToMasterNettingArrangement	19000000	usd
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CY2021Q2	us-gaap	Derivative Liability Not Subject To Master Netting Arrangement DerivativeLiabilityNotSubjectToMasterNettingArrangement	2000000	usd
CY2021Q2	us-gaap	Derivative Liability Not Subject To Master Netting Arrangement DerivativeLiabilityNotSubjectToMasterNettingArrangement	2000000	usd
CY2022Q2	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	79000000	usd
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CY2022Q2	us-gaap	Derivative Asset Fair Value Offset Against Collateral Net Of Not Subject To Master Netting Arrangement Policy Election DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection	24000000	usd
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CY2021Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-28000000	usd
CY2021Q4	us-gaap	Derivative Asset Fair Value Offset Against Collateral Net Of Not Subject To Master Netting Arrangement Policy Election DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection	22000000	usd
CY2021Q2	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	76000000	usd
CY2021Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	-31000000	usd
CY2021Q2	us-gaap	Derivative Asset Fair Value Offset Against Collateral Net Of Not Subject To Master Netting Arrangement Policy Election DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection	45000000	usd
CY2022Q2	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	83000000	usd
CY2022Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	55000000	usd
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CY2021Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	28000000	usd
CY2021Q4	us-gaap	Derivative Liability Fair Value Offset Against Collateral Net Of Not Subject To Master Netting Arrangement Policy Election DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection	72000000	usd
CY2021Q2	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	104000000	usd
CY2021Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	31000000	usd
CY2021Q2	us-gaap	Derivative Liability Fair Value Offset Against Collateral Net Of Not Subject To Master Netting Arrangement Policy Election DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection	73000000	usd
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CY2021Q2	us-gaap	Derivative Liability Fair Value Of Collateral DerivativeLiabilityFairValueOfCollateral	104000000	usd
CY2022Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	107300000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	102700000	shares
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CY2022Q2	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	400000	shares
CY2021Q2	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	700000	shares
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	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	600000	shares
CY2022Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	107700000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	103400000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	107100000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	102400000	shares
CY2022Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	257000000.0	usd
CY2022Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.196
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	223800000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	493900000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	416300000	usd
CY2022Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.40
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.18
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.63
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.09
CY2022Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.39
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.17
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.61
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.07
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2021Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.190
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.195
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.185
CY2022Q2	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	223000000	usd
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	202000000	usd
CY2021Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	21000000	usd
CY2022Q2	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	223000000	usd
CY2022Q2	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	usd
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	usd
CY2022Q2	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	722000000	usd
CY2021Q4	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	631000000	usd
CY2022Q2	us-gaap	Investment Related Liabilities InvestmentRelatedLiabilities	424000000	usd
CY2021Q4	us-gaap	Investment Related Liabilities InvestmentRelatedLiabilities	361000000	usd
CY2022Q2	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	15400000	usd
CY2021Q2	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	8200000	usd
	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	28800000	usd
	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	23700000	usd
	us-gaap	Line Of Credit Facility Expiration Period LineOfCreditFacilityExpirationPeriod	P1Y
CY2022Q2	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Face Amount Liability FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability	17395000000	usd
CY2021Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Face Amount Liability FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability	13901000000	usd
	wal	Maximum Loan To Value Ratio MaximumLoanToValueRatio	0.75
CY2022Q2	wal	Percentage Of Commercial Real Estate Loans Occupied By Owners PercentageOfCommercialRealEstateLoansOccupiedByOwners	0.19
CY2021Q4	wal	Percentage Of Commercial Real Estate Loans Occupied By Owners PercentageOfCommercialRealEstateLoansOccupiedByOwners	0.23
CY2022Q2	us-gaap	Lease Cost LeaseCost	6200000	usd
	us-gaap	Lease Cost LeaseCost	12100000	usd
CY2021Q2	us-gaap	Lease Cost LeaseCost	4400000	usd
	us-gaap	Lease Cost LeaseCost	8100000	usd
CY2022Q2	wal	Lesseeoperatingleaseothercost Lesseeoperatingleaseothercost	1000000	usd
	wal	Lesseeoperatingleaseothercost Lesseeoperatingleaseothercost	2100000	usd
CY2021Q2	wal	Lesseeoperatingleaseothercost Lesseeoperatingleaseothercost	900000	usd
	wal	Lesseeoperatingleaseothercost Lesseeoperatingleaseothercost	1900000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-2000000.0	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-200000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	4200000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-500000	usd
CY2022Q2	us-gaap	Fair Value Liabilities Measured On Recurring Basis Subordinated Debt Obligations FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations	62000000	usd
CY2022Q2	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	6000000	usd
CY2021Q4	us-gaap	Fair Value Liabilities Measured On Recurring Basis Subordinated Debt Obligations FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations	67000000	usd
CY2021Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	39000000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-2000000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-200000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	4200000	usd
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	-500000	usd
CY2022Q2	wal	Fair Value Option Loans Held As Assets Current Through89 Days FairValueOptionLoansHeldAsAssetsCurrentThrough89Days	2602000000	usd
CY2022Q2	wal	Fair Value Option Loans Held As Assets Upb Current Through89 Days FairValueOptionLoansHeldAsAssetsUPBCurrentThrough89Days	2552000000	usd
CY2022Q2	wal	Fair Value Option Loans Held As Assets Current Through89 Days Aggregate Difference FairValueOptionLoansHeldAsAssetsCurrentThrough89DaysAggregateDifference	50000000	usd
CY2021Q4	wal	Fair Value Option Loans Held As Assets Current Through89 Days FairValueOptionLoansHeldAsAssetsCurrentThrough89Days	3938000000	usd
CY2021Q4	wal	Fair Value Option Loans Held As Assets Upb Current Through89 Days FairValueOptionLoansHeldAsAssetsUPBCurrentThrough89Days	3808000000	usd
CY2021Q4	wal	Fair Value Option Loans Held As Assets Current Through89 Days Aggregate Difference FairValueOptionLoansHeldAsAssetsCurrentThrough89DaysAggregateDifference	130000000	usd
CY2022Q2	us-gaap	Fair Value Option Loans Held As Assets90 Days Or More Past Due FairValueOptionLoansHeldAsAssets90DaysOrMorePastDue	2000000	usd
CY2022Q2	wal	Fair Value Option Loans Held As Assets Upb90 Days Or More Past Due FairValueOptionLoansHeldAsAssetsUPB90DaysOrMorePastDue	2000000	usd
CY2022Q2	us-gaap	Fair Value Option Loans Held As Assets90 Days Or More Past Due Aggregate Difference FairValueOptionLoansHeldAsAssets90DaysOrMorePastDueAggregateDifference	0	usd
CY2021Q4	us-gaap	Fair Value Option Loans Held As Assets90 Days Or More Past Due FairValueOptionLoansHeldAsAssets90DaysOrMorePastDue	2000000	usd
CY2021Q4	wal	Fair Value Option Loans Held As Assets Upb90 Days Or More Past Due FairValueOptionLoansHeldAsAssetsUPB90DaysOrMorePastDue	2000000	usd
CY2021Q4	us-gaap	Fair Value Option Loans Held As Assets90 Days Or More Past Due Aggregate Difference FairValueOptionLoansHeldAsAssets90DaysOrMorePastDueAggregateDifference	0	usd
CY2022Q2	wal	Fair Value Option Loans Held As Assets FairValueOptionLoansHeldAsAssets	2604000000	usd
CY2022Q2	us-gaap	Fair Value Option Loans Held As Assets Aggregate Difference FairValueOptionLoansHeldAsAssetsAggregateDifference	50000000	usd
CY2021Q4	wal	Fair Value Option Loans Held As Assets FairValueOptionLoansHeldAsAssets	3940000000	usd
CY2021Q4	us-gaap	Fair Value Option Loans Held As Assets Aggregate Difference FairValueOptionLoansHeldAsAssetsAggregateDifference	130000000	usd
CY2022Q2	wal	Cash Cash Equivalentsand Investment Securities CashCashEquivalentsandInvestmentSecurities	10688000000	usd
CY2022Q2	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	2803000000	usd
CY2022Q2	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	48572000000	usd
CY2022Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	273000000	usd
CY2022Q2	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	48299000000	usd
CY2022Q2	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	12000000	usd
CY2022Q2	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	695000000	usd
CY2022Q2	wal	Other Assets Segment OtherAssetsSegment	3558000000	usd
CY2022Q2	us-gaap	Assets Assets	66055000000	usd
CY2022Q2	us-gaap	Deposits Deposits	53712000000	usd
CY2022Q2	wal	Borrowingsand Qualifying Debt BorrowingsandQualifyingDebt	6101000000	usd
CY2022Q2	wal	Other Liabilities Segment OtherLiabilitiesSegment	1283000000	usd
CY2022Q2	us-gaap	Liabilities Liabilities	61096000000	usd
CY2022Q2	us-gaap	Stockholders Equity StockholdersEquity	4959000000	usd
CY2022Q2	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	66055000000	usd
CY2022Q2	wal	Excess Funds Providedby Usedin Segment Basis ExcessFundsProvidedbyUsedinSegmentBasis	0	usd
CY2022Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	525000000.0	usd
CY2022Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	27500000	usd
CY2022Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	497500000	usd
CY2022Q2	us-gaap	Noninterest Income NoninterestIncome	95000000.0	usd
CY2022Q2	us-gaap	Noninterest Expense NoninterestExpense	268900000	usd
CY2022Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	323600000	usd
CY2022Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	63400000	usd
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	260200000	usd
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	974500000	usd
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	36500000	usd
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	938000000.0	usd
	us-gaap	Noninterest Income NoninterestIncome	201300000	usd
	us-gaap	Noninterest Expense NoninterestExpense	517500000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	621800000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	121500000	usd
	us-gaap	Net Income Loss NetIncomeLoss	500300000	usd
CY2021Q4	wal	Cash Cash Equivalentsand Investment Securities CashCashEquivalentsandInvestmentSecurities	8057000000	usd
CY2021Q4	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	5635000000	usd
CY2021Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	39075000000	usd
CY2021Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	252000000	usd
CY2021Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	38823000000	usd
CY2021Q4	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	12000000	usd
CY2021Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	635000000	usd
CY2021Q4	wal	Other Assets Segment OtherAssetsSegment	2821000000	usd
CY2021Q4	us-gaap	Assets Assets	55983000000	usd
CY2021Q4	us-gaap	Deposits Deposits	47612000000	usd
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	734700000	usd
	us-gaap	Noninterest Income NoninterestIncome	155700000	usd
CY2021Q4	wal	Borrowingsand Qualifying Debt BorrowingsandQualifyingDebt	2398000000	usd
CY2021Q4	wal	Other Liabilities Segment OtherLiabilitiesSegment	1010000000	usd
CY2021Q4	us-gaap	Liabilities Liabilities	51020000000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	4963000000	usd
CY2021Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	55983000000	usd
CY2021Q4	wal	Excess Funds Providedby Usedin Segment Basis ExcessFundsProvidedbyUsedinSegmentBasis	0	usd
CY2021Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	370500000	usd
CY2021Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	14500000	usd
CY2021Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	385000000.0	usd
CY2021Q2	us-gaap	Noninterest Income NoninterestIncome	136000000.0	usd
CY2021Q2	us-gaap	Noninterest Expense NoninterestExpense	244800000	usd
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	276200000	usd
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	52400000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	223800000	usd
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	687800000	usd
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	46900000	usd
	us-gaap	Noninterest Expense NoninterestExpense	379800000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	510600000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	94300000	usd
	us-gaap	Net Income Loss NetIncomeLoss	416300000	usd
CY2022Q2	wal	Revenue From Contracts With Customers RevenueFromContractsWithCustomers	11300000	usd
CY2021Q2	wal	Revenue From Contracts With Customers RevenueFromContractsWithCustomers	9200000	usd
	wal	Revenue From Contracts With Customers RevenueFromContractsWithCustomers	25600000	usd
	wal	Revenue From Contracts With Customers RevenueFromContractsWithCustomers	18400000	usd

Files In Submission

Name	View Source	Status
0001212545-22-000130-index-headers.html	Edgar Link	pending
0001212545-22-000130-index.html	Edgar Link	pending
0001212545-22-000130.txt	Edgar Link	pending
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walex3116302022.htm	Edgar Link	pending
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walex326302022.htm	Edgar Link	pending

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$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal

2022 Q3 Form 10-Q Financial Statement

#000121254522000130 Filed on July 29, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WAL WESTERN ALLIANCE BANCORPORATION Stock $wal

2022 Q3 Form 10-Q Financial Statement

#000121254522000130 Filed on July 29, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal