$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal

$wal Overview Financials Valuation SEC Filings Company Website

2021 Q1 Form 10-Q Financial Statement

#000121254521000127 Filed on April 30, 2021

Income Statement

Concept	2021 Q1	2020 Q1
Revenue	$334.1M	$307.2M
YoY Change	8.76%	5.53%
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	$6.000M	$5.000M
YoY Change	20.0%	19.05%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$16.80M	$38.20M
YoY Change	-56.02%	-12.79%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$234.4M	$102.4M
YoY Change	128.91%	-30.01%
Income Tax	$41.90M	$18.50M
% Of Pretax Income	17.88%	18.07%
Net Earnings	$192.5M	$83.90M
YoY Change	129.44%	-30.55%
Net Earnings / Revenue	57.62%	27.31%
Basic Earnings Per Share	$1.91	$0.83
Diluted Earnings Per Share	$1.90	$0.83
COMMON SHARES
Basic Shares Outstanding	100.8M shares	101.3M shares
Diluted Shares Outstanding	101.4M shares	101.7M shares

Balance Sheet

Concept	2021 Q1	2020 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$5.347B	$415.7M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$138.4M	$125.9M
YoY Change	9.94%	5.06%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$193.0M	$131.0M
YoY Change	47.33%	11.02%
Other Assets	$50.00M	$28.00M
YoY Change	78.57%	27.27%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$43.40B	$29.16B
YoY Change	48.83%	22.55%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$85.00M	$79.00M
YoY Change	7.59%	1.28%
Deferred Revenue
YoY Change
Short-Term Debt	$5.000M	$308.0M
YoY Change	-98.38%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$85.00M	$79.00M
YoY Change	7.59%	1.28%
LONG-TERM LIABILITIES
Long-Term Debt	$544.0M	$698.0M
YoY Change	-22.06%	86.63%
Other Long-Term Liabilities	$642.0M	$528.0M
YoY Change	21.59%	33.0%
Total Long-Term Liabilities	$1.186B	$1.226B
YoY Change	-3.26%	59.01%
TOTAL LIABILITIES
Total Short-Term Liabilities	$85.00M	$79.00M
Total Long-Term Liabilities	$1.186B	$1.226B
Total Liabilities	$39.68B	$26.16B
YoY Change	51.71%	24.14%
SHAREHOLDERS EQUITY
Retained Earnings	$2.169B	$1.680B
YoY Change	29.06%	20.09%
Common Stock	$1.608B	$10.00K
YoY Change	16081900.0%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$84.00M	$70.19M
YoY Change	19.68%	15.09%
Treasury Stock Shares	2.324M shares
Shareholders Equity	$3.713B	$2.992B
YoY Change
Total Liabilities & Shareholders Equity	$43.40B	$29.16B
YoY Change	48.83%	22.55%

Cashflow Statement

Concept	2021 Q1	2020 Q1
OPERATING ACTIVITIES
Net Income	$192.5M	$83.90M
YoY Change	129.44%	-30.55%
Depreciation, Depletion And Amortization	$6.000M	$5.000M
YoY Change	20.0%	19.05%
Cash From Operating Activities	$100.1M	$124.0M
YoY Change	-19.27%	-18.05%
INVESTING ACTIVITIES
Capital Expenditures	-$10.40M	-$16.60M
YoY Change	-37.35%	418.75%
Acquisitions	$0.00
YoY Change
Other Investing Activities	-$4.049B	-$2.379B
YoY Change	70.16%	583.12%
Cash From Investing Activities	-$4.059B	-$2.396B
YoY Change	69.41%	581.65%
FINANCING ACTIVITIES
Cash Dividend Paid	$25.30M
YoY Change
Common Stock Issuance & Retirement, Net	-$209.2M	$62.50M
YoY Change	-434.72%	64.69%
Debt Paid & Issued, Net	$0.00
YoY Change
Cash From Financing Activities	$6.634B	$2.253B
YoY Change	194.43%	362.43%
NET CHANGE
Cash From Operating Activities	$100.1M	$124.0M
Cash From Investing Activities	-$4.059B	-$2.396B
Cash From Financing Activities	$6.634B	$2.253B
Net Change In Cash	$2.675B	-$18.90M
YoY Change	-14252.38%	-106.58%
FREE CASH FLOW
Cash From Operating Activities	$100.1M	$124.0M
Capital Expenditures	-$10.40M	-$16.60M
Free Cash Flow	$110.5M	$140.6M
YoY Change	-21.41%	-9.01%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021Q1	dei	Amendment Flag AmendmentFlag	false
CY2021Q1	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021Q1	dei	Document Type DocumentType	10-Q
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CY2021Q1	dei	Document Quarterly Report DocumentQuarterlyReport	true
CY2021Q1	dei	Document Period End Date DocumentPeriodEndDate	2021-03-31
CY2021Q1	dei	Document Transition Report DocumentTransitionReport	false
CY2021Q1	dei	Entity File Number EntityFileNumber	001-32550
CY2021Q1	dei	Entity Registrant Name EntityRegistrantName	WESTERN ALLIANCE BANCORPORATION
CY2021Q1	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021Q1	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	88-0365922
CY2021Q1	dei	Entity Address Address Line1 EntityAddressAddressLine1	One E. Washington Street, Suite 1400
CY2021Q1	dei	Entity Address City Or Town EntityAddressCityOrTown	Phoenix
CY2021Q1	dei	Entity Address State Or Province EntityAddressStateOrProvince	AZ
CY2021Q1	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	85004
CY2021Q1	dei	City Area Code CityAreaCode	602
CY2021Q1	dei	Local Phone Number LocalPhoneNumber	389-3500
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CY2021Q1	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2021Q1	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2021Q1	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
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CY2020Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	2000000.0	USD
CY2021Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-72000000.0	USD
CY2020Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	6300000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0.0	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	100000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	0	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	300000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	100000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodTax	2100000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	300000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	6600000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-0.0	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0.0	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	100000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	100000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-72400000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12500000	USD
CY2021Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	120100000	USD
CY2020Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	96400000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	3016700000	USD
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	2991800000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	83900000	USD
CY2020Q1	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	7000000.0	USD
CY2020Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	7500000	USD
CY2020Q1	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	62500000	USD
CY2020Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	25600000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12500000	USD
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	2999600000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	3413500000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	192500000	USD
CY2021Q1	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	8100000	USD
CY2021Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	12900000	USD
CY2021Q1	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	-209200000	USD
CY2021Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	25300000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-72400000	USD
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	3712700000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	192500000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	83900000	USD
CY2021Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-32400000	USD
CY2020Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	51200000	USD
CY2021Q1	us-gaap	Depreciation And Amortization DepreciationAndAmortization	6000000.0	USD
CY2020Q1	us-gaap	Depreciation And Amortization DepreciationAndAmortization	5400000	USD
CY2021Q1	us-gaap	Share Based Compensation ShareBasedCompensation	8000000.0	USD
CY2020Q1	us-gaap	Share Based Compensation ShareBasedCompensation	6900000	USD
CY2021Q1	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	5100000	USD
CY2020Q1	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-4800000	USD
CY2021Q1	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-10700000	USD
CY2020Q1	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-5600000	USD
CY2021Q1	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	15500000	USD
CY2020Q1	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	7400000	USD
CY2021Q1	us-gaap	Operating Lease Expense OperatingLeaseExpense	3000000.0	USD
CY2020Q1	us-gaap	Operating Lease Expense OperatingLeaseExpense	2800000	USD
CY2021Q1	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	19200000	USD
CY2020Q1	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	4100000	USD
CY2021Q1	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1000000.0	USD
CY2020Q1	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1000000.0	USD
CY2021Q1	wal	Gain Loss On Sale And Valuation Of Investment Securities And Other Assets Net GainLossOnSaleAndValuationOfInvestmentSecuritiesAndOtherAssetsNet	-1100000	USD
CY2020Q1	wal	Gain Loss On Sale And Valuation Of Investment Securities And Other Assets Net GainLossOnSaleAndValuationOfInvestmentSecuritiesAndOtherAssetsNet	-9700000	USD
CY2021Q1	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	-700000	USD
CY2020Q1	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	0	USD
CY2021Q1	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	89900000	USD
CY2020Q1	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	39000000.0	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	100100000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	124000000.0	USD
CY2021Q1	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	2748500000	USD
CY2020Q1	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	654500000	USD
CY2021Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	493600000	USD
CY2020Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	264600000	USD
CY2021Q1	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	0	USD
CY2020Q1	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	62300000	USD
CY2021Q1	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	131600000	USD
CY2020Q1	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	24200000	USD
CY2021Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	700000	USD
CY2020Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1300000	USD
CY2021Q1	wal	Paymentsto Acquire Securities Equity PaymentstoAcquireSecuritiesEquity	28300000	USD
CY2020Q1	wal	Paymentsto Acquire Securities Equity PaymentstoAcquireSecuritiesEquity	7500000	USD
CY2021Q1	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	400000	USD
CY2020Q1	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	4200000	USD
CY2021Q1	wal	Proceedsfrom Saleof Equitysecurities Fvni ProceedsfromSaleofEquitysecuritiesFVNI	600000	USD
CY2020Q1	wal	Proceedsfrom Saleof Equitysecurities Fvni ProceedsfromSaleofEquitysecuritiesFVNI	0	USD
CY2021Q1	wal	Purchase Of Investment Tax Credits PurchaseOfInvestmentTaxCredits	22600000	USD
CY2020Q1	wal	Purchase Of Investment Tax Credits PurchaseOfInvestmentTaxCredits	37400000	USD
CY2021Q1	wal	Purchaseof Sbic Investments PurchaseofSBICInvestments	1700000	USD
CY2020Q1	wal	Purchaseof Sbic Investments PurchaseofSBICInvestments	2100000	USD
CY2021Q1	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1611100000	USD
CY2020Q1	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1991100000	USD
CY2021Q1	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	10400000	USD
CY2020Q1	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	11500000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-4058900000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2395900000	USD
CY2021Q1	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	6462600000	USD
CY2020Q1	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	2034200000	USD
CY2021Q1	us-gaap	Proceeds From Repayments Of Debt ProceedsFromRepaymentsOfDebt	-100000	USD
CY2020Q1	us-gaap	Proceeds From Repayments Of Debt ProceedsFromRepaymentsOfDebt	314300000	USD
CY2021Q1	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	12800000	USD
CY2020Q1	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	7400000	USD
CY2021Q1	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2020Q1	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	62500000	USD
CY2021Q1	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	25300000	USD
CY2020Q1	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	25600000	USD
CY2021Q1	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	209200000	USD
CY2020Q1	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	6633600000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	2253000000.0	USD
CY2021Q1	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	2674800000	USD
CY2020Q1	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-18900000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2671700000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	434600000	USD
CY2021Q1	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	5346500000	USD
CY2020Q1	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	415700000	USD
CY2021Q1	us-gaap	Interest Paid InterestPaid	15000000.0	USD
CY2020Q1	us-gaap	Interest Paid InterestPaid	46300000	USD
CY2021Q1	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	30800000	USD
CY2020Q1	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1300000	USD
CY2021Q1	wal	Number Of Wholly Owned Subsidiaries Non Bank Subsidiaries NumberOfWhollyOwnedSubsidiariesNonBankSubsidiaries	2	Subsidiary
CY2021Q1	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.
CY2021Q1	wal	Number Of Unconsolidated Subsidiaries NumberOfUnconsolidatedSubsidiaries	8	Subsidiary
CY2021Q1	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-top:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Reclassifications</span></div><div style="margin-top:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Certain amounts reported in prior periods may have been reclassified in the Consolidated Financial Statements to conform to the current presentation. The reclassifications have no effect on net income or stockholders’ equity as previously reported.</span></div>
CY2021Q1	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	698000000.0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	43800000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	1400000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	740400000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6913300000	USD
CY2021Q1	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	105100000	USD
CY2021Q1	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	78500000	USD
CY2021Q1	us-gaap	Available For Sale Securities AvailableForSaleSecurities	6939900000	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	187100000	USD
CY2021Q1	wal	Equitysecurities Fvni Accumulated Gross Unrealized Gain Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedGainBeforeTax	6200000	USD
CY2021Q1	wal	Equitysecurities Fvni Accumulated Gross Unrealized Loss Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedLossBeforeTax	400000	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	192900000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	568800000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	43000000.0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	611800000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	4586400000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	137600000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	15500000	USD
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	4708500000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	160100000	USD
CY2020Q4	wal	Equitysecurities Fvni Accumulated Gross Unrealized Gain Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedGainBeforeTax	7600000	USD
CY2020Q4	wal	Equitysecurities Fvni Accumulated Gross Unrealized Loss Before Tax EquitysecuritiesFVNIAccumulatedGrossUnrealizedLossBeforeTax	400000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	167300000	USD
CY2021Q1	us-gaap	Pledged Financial Instruments Not Separately Reported Other Debt Securities Available For Sale Or Held For Investment PledgedFinancialInstrumentsNotSeparatelyReportedOtherDebtSecuritiesAvailableForSaleOrHeldForInvestment	693200000	USD
CY2020Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Other Debt Securities Available For Sale Or Held For Investment PledgedFinancialInstrumentsNotSeparatelyReportedOtherDebtSecuritiesAvailableForSaleOrHeldForInvestment	778000000.0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1400000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	48000000.0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	1400000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	48000000.0	USD
CY2021Q1	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	67700000	USD
CY2021Q1	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	2924100000	USD
CY2021Q1	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	10800000	USD
CY2021Q1	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	131200000	USD
CY2021Q1	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	78500000	USD
CY2021Q1	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	3055300000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	4400000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	398900000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	11100000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	120800000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	15500000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	519700000	USD
CY2021Q1	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	187	positions
CY2020Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	49	positions
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	6800000	USD
CY2021Q1	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	2400000	USD
CY2021Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityAllowanceForCreditLossWriteoff	0	USD
CY2021Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityAllowanceForCreditLossRecovery	0	USD
CY2021Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	9200000	USD
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	2600000	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	300000	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityAllowanceForCreditLossWriteoff	0	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityAllowanceForCreditLossRecovery	0	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	2900000	USD
CY2021Q1	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	2400000	USD
CY2020Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	2000000.0	USD
CY2021Q1	us-gaap	Available For Sale Securities AvailableForSaleSecurities	6939900000	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	192900000	USD
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	4708500000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	167300000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	10700000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	10700000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	31300000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	31800000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	656000000.0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	697900000	USD
CY2021Q1	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	698000000.0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	740400000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	50000000.0	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	50000000.0	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	38000000.0	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	38500000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	780500000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	780800000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	1773300000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	1832600000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	4271500000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	4238000000.0	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6913300000	USD
CY2021Q1	us-gaap	Available For Sale Securities AvailableForSaleSecurities	6939900000	USD
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CY2021Q1	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	247100000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	278900000	USD
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CY2020Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	75400000	USD
CY2020Q4	us-gaap	Receivable With Imputed Interest Premium ReceivableWithImputedInterestPremium	26000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	100800000	USD
CY2021Q1	wal	Financing Receivable Nonaccrual With Allowance FinancingReceivableNonaccrualWithAllowance	12800000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	113600000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
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CY2020Q4	wal	Financing Receivable Nonaccrual With Allowance FinancingReceivableNonaccrualWithAllowance	10300000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	115200000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	1500000	USD
CY2020Q1	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	700000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	28703700000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	7300000	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	28711000000.0	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	27041800000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	11200000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	27053000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	2468500000	USD
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CY2021Q1	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	4516000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	2592300000	USD
CY2021Q1	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	1486800000	USD
CY2021Q1	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	2346700000	USD
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CY2021Q1	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	28711000000.0	USD
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CY2020Q4	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	2939200000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	1669000000.0	USD
CY2020Q4	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	691400000	USD
CY2021Q1	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	SecurityLoan
CY2020Q4	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	1892400000	USD
CY2020Q4	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	8919500000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	27053000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	60200000	USD
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	61600000	USD
CY2021Q1	wal	Reserves Allocated To Customers Whose Loan Terms Modified In Troubled Debt Restructurings ReservesAllocatedToCustomersWhoseLoanTermsModifiedInTroubledDebtRestructurings	3100000	USD
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CY2021Q1	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	300000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	600000	USD
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CY2021Q1	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	60200000	USD
CY2021Q1	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	3	SecurityLoan
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CY2020Q1	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	26500000	USD
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CY2020Q1	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	700000	USD
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CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	2100000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	700000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	247100000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	186900000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	45200000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	100000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	3300000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	235300000	USD
CY2021Q1	us-gaap	Interest Receivable InterestReceivable	138100000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	142100000	USD
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CY2021Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	32600000	USD
CY2020Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	29600000	USD
CY2021Q1	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	28393000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	318000000.0	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	28711000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	233900000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	13200000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	247100000	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	26787400000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	265600000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	27053000000.0	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	267700000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	11200000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	278900000	USD
CY2021Q1	us-gaap	Financing Receivable Significant Purchases FinancingReceivableSignificantPurchases	1301100000	USD
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CY2021Q1	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	100100000	USD
CY2020Q1	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	0	USD
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CY2020Q1	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	139111	shares
CY2020Q1	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	53.61
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	92300000	USD
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CY2021Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	19900000	USD
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CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12500000	USD
CY2020Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	37500000	USD
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CY2020Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	100000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0.0	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0.0	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	100000	USD
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CY2021Q1	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	1543400000	USD
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CY2020Q4	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	1587100000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	6600000	USD
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CY2020Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	101700000	shares
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CY2021Q1	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	487900000	USD
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CY2021Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	300000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Unrealized Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionUnrealizedGainLossArisingDuringPeriodAfterTax	6600000	USD
CY2021Q1	us-gaap	Fair Value Liabilities Measured On Recurring Basis Subordinated Debt Obligations FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations	66300000	USD
CY2021Q1	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	46800000	USD
CY2021Q1	us-gaap	Hedged Liability Fair Value Hedge Cumulative Increase Decrease HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease	3000000.0	USD
CY2020Q4	us-gaap	Fair Value Liabilities Measured On Recurring Basis Subordinated Debt Obligations FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations	65900000	USD
CY2020Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	85500000	USD
CY2020Q4	us-gaap	Hedged Liability Fair Value Hedge Cumulative Increase Decrease HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease	-2700000	USD
CY2020Q4	wal	Percentage Of Commercial Real Estate Loans Occupied By Owners PercentageOfCommercialRealEstateLoansOccupiedByOwners	0.28
CY2020Q4	us-gaap	Investment Related Liabilities InvestmentRelatedLiabilities	151700000	USD
CY2021Q1	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	15500000	USD
CY2020Q1	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	7400000	USD
CY2021Q1	us-gaap	Line Of Credit Facility Expiration Period LineOfCreditFacilityExpirationPeriod	P1Y
CY2021Q1	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Face Amount Liability FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability	10026000000.0	USD
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Face Amount Liability FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability	9903600000	USD
CY2021Q1	wal	Maximum Loan To Value Ratio MaximumLoanToValueRatio	0.75
CY2021Q1	wal	Percentage Of Commercial Real Estate Loans Occupied By Owners PercentageOfCommercialRealEstateLoansOccupiedByOwners	0.27
CY2021Q1	us-gaap	Lease Cost LeaseCost	3700000	USD
CY2020Q1	us-gaap	Lease Cost LeaseCost	3400000	USD
CY2021Q1	wal	Lesseeoperatingleaseothercost Lesseeoperatingleaseothercost	1000000.0	USD
CY2020Q1	wal	Lesseeoperatingleaseothercost Lesseeoperatingleaseothercost	1100000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	5000000.0	USD
CY2021Q1	us-gaap	Short Term Borrowings ShortTermBorrowings	5000000.0	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	5000000.0	USD
CY2021Q1	us-gaap	Federal Funds Purchased FederalFundsPurchased	0	USD
CY2021Q1	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	5000000.0	USD
CY2021Q1	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	15900000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	16000000.0	USD
CY2021Q1	us-gaap	Subordinated Debt SubordinatedDebt	464400000	USD
CY2020Q4	us-gaap	Subordinated Debt SubordinatedDebt	469800000	USD
CY2021Q1	wal	Numberof Statutory Business Trusts Formedor Acquired NumberofStatutoryBusinessTrustsFormedorAcquired	8	Trust
CY2021Q1	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	79300000	USD
CY2020Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	78900000	USD
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	152418	shares
CY2021Q1	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	2300000	shares
CY2021Q1	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	-209200000	USD
CY2021Q1	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	250000000.0	USD
CY2021Q1	wal	Collateral Dependent Loans Allowance CollateralDependentLoansAllowance	-9500000	USD
CY2021Q1	wal	Cash Cash Equivalentsand Investment Securities CashCashEquivalentsandInvestmentSecurities	13235300000	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	28711000000.0	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	247100000	USD
CY2021Q1	wal	Loansand Leases Receivable Including Heldfor Sale Net LoansandLeasesReceivableIncludingHeldforSaleNet	28463900000	USD
CY2021Q1	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	4200000	USD
CY2021Q1	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	298000000.0	USD
CY2021Q1	wal	Other Assets Segment OtherAssetsSegment	1395600000	USD
CY2021Q1	us-gaap	Assets Assets	43397000000.0	USD
CY2021Q1	us-gaap	Deposits Deposits	38393100000	USD
CY2021Q1	wal	Borrowingsand Qualifying Debt BorrowingsandQualifyingDebt	548700000	USD
CY2021Q1	wal	Other Liabilities Segment OtherLiabilitiesSegment	742500000	USD
CY2021Q1	us-gaap	Liabilities Liabilities	39684300000	USD
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	3712700000	USD
CY2021Q1	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	43397000000.0	USD
CY2021Q1	wal	Excess Funds Providedby Usedin Segment Basis ExcessFundsProvidedbyUsedinSegmentBasis	0	USD
CY2021Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	317300000	USD
CY2021Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-32400000	USD
CY2021Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	349700000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	19700000	USD
CY2021Q1	us-gaap	Noninterest Expense NoninterestExpense	135000000.0	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	234400000	USD
CY2021Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	41900000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	192500000	USD
CY2020Q4	wal	Cash Cash Equivalentsand Investment Securities CashCashEquivalentsandInvestmentSecurities	8176500000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	27053000000.0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	278900000	USD
CY2020Q4	wal	Loansand Leases Receivable Including Heldfor Sale Net LoansandLeasesReceivableIncludingHeldforSaleNet	26774100000	USD
CY2020Q4	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	1400000	USD
CY2020Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	298500000	USD
CY2020Q4	wal	Other Assets Segment OtherAssetsSegment	1210500000	USD
CY2020Q4	us-gaap	Assets Assets	36461000000.0	USD
CY2020Q4	us-gaap	Deposits Deposits	31930500000	USD
CY2020Q4	wal	Borrowingsand Qualifying Debt BorrowingsandQualifyingDebt	553700000	USD
CY2020Q4	wal	Other Liabilities Segment OtherLiabilitiesSegment	563300000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	33047500000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	3413500000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	36461000000.0	USD
CY2020Q4	wal	Excess Funds Providedby Usedin Segment Basis ExcessFundsProvidedbyUsedinSegmentBasis	0	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	269000000.0	USD
CY2020Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	51200000	USD
CY2020Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	217800000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	5100000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	120500000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	102400000	USD
CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18500000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	83900000	USD
CY2021Q1	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	6700000	USD
CY2021Q1	wal	Debitandcreditcardinterchangefees Debitandcreditcardinterchangefees	1300000	USD
CY2021Q1	wal	Success Fees SuccessFees	1000000.0	USD
CY2021Q1	wal	Othernoninterestincome Othernoninterestincome	200000	USD
CY2021Q1	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	9200000	USD
CY2021Q1	wal	Otherrevenue Otherrevenue	10500000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	19700000	USD
CY2020Q1	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	6400000	USD
CY2020Q1	wal	Debitandcreditcardinterchangefees Debitandcreditcardinterchangefees	1400000	USD
CY2020Q1	wal	Success Fees SuccessFees	100000	USD
CY2020Q1	wal	Othernoninterestincome Othernoninterestincome	100000	USD
CY2020Q1	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	8000000.0	USD
CY2020Q1	wal	Otherrevenue Otherrevenue	-2900000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	5100000	USD
CY2021Q1	us-gaap	Accounts Receivable Net AccountsReceivableNet	1700000	USD
CY2020Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	1600000	USD
CY2021Q2	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	1220000000	USD

Files In Submission

Name	View Source	Status
0001212545-21-000127-index-headers.html	Edgar Link	pending
0001212545-21-000127-index.html	Edgar Link	pending
0001212545-21-000127.txt	Edgar Link	pending
0001212545-21-000127-xbrl.zip	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
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report.css	Edgar Link	pending
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wal-20210331.htm	Edgar Link	pending
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wal-20210331_cal.xml	Edgar Link	unprocessable
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wal-20210331_htm.xml	Edgar Link	completed
wal-20210331_lab.xml	Edgar Link	unprocessable
wal-20210331_pre.xml	Edgar Link	unprocessable
walex3113312021.htm	Edgar Link	pending
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walex323312021.htm	Edgar Link	pending

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$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal

2021 Q1 Form 10-Q Financial Statement

#000121254521000127 Filed on April 30, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WAL WESTERN ALLIANCE BANCORPORATION Stock $wal

2021 Q1 Form 10-Q Financial Statement

#000121254521000127 Filed on April 30, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WAL
WESTERN ALLIANCE BANCORPORATION Stock $wal