$WABC
Westamerica Bancorp Stock $wabc

$wabc Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-Q Financial Statement

#000117184320007649 Filed on November 05, 2020

Income Statement

Concept	2020 Q4	2020 Q3	2019 Q3
Revenue	$42.96M	$41.37M	$39.70M
YoY Change	7.73%	4.21%	2.8%
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	$4.100M	$6.100M	$5.300M
YoY Change	-24.07%	15.09%	-17.19%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$466.0K	$455.0K
YoY Change		2.42%	-13.66%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$31.89M	$26.77M	$27.02M
YoY Change	18.35%	-0.9%	27.14%
Income Tax	$8.100M	$6.721M	$6.626M
% Of Pretax Income	25.4%	25.1%	24.53%
Net Earnings	$23.84M	$20.05M	$20.39M
YoY Change	15.0%	-1.66%	19.99%
Net Earnings / Revenue	55.49%	48.47%	51.37%
Basic Earnings Per Share	$0.89	$0.74	$0.76
Diluted Earnings Per Share	$0.89	$0.74	$0.75
COMMON SHARES
Basic Shares Outstanding	26.87M	26.93M	26.99M
Diluted Shares Outstanding		26.95M	27.03M

Balance Sheet

Concept	2020 Q4	2020 Q3	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$621.3M	$399.0M	$415.6M
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	$32.81M	$33.44M	$34.08M
YoY Change	-5.16%	-1.89%	-3.7%
Goodwill	$121.7M	$121.7M	$121.7M
YoY Change	0.0%	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments	$14.20M	$14.20M	$14.20M
YoY Change	0.0%	0.0%	0.0%
Other Assets	$0.00	$0.00	$11.90M
YoY Change	-100.0%	-100.0%	-75.51%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$6.748B	$6.563B	$5.616B
YoY Change	20.08%	16.87%	1.57%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$18.80M	$19.10M	$19.70M
YoY Change	9.94%	-3.05%
Deferred Revenue
YoY Change
Short-Term Debt	$102.5M	$108.0M	$45.65M
YoY Change	231.56%	136.54%	-26.09%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$18.80M	$19.10M	$19.70M
YoY Change	9.94%	-3.05%	-68.12%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$68.00M	$49.60M	$40.70M
YoY Change	147.27%	21.87%	3.56%
Total Long-Term Liabilities	$68.00M	$49.60M	$40.70M
YoY Change	147.27%	21.87%	3.56%
TOTAL LIABILITIES
Total Short-Term Liabilities	$18.80M	$19.10M	$19.70M
Total Long-Term Liabilities	$68.00M	$49.60M	$40.70M
Total Liabilities	$5.903B	$5.738B	$4.903B
YoY Change	20.76%	17.03%	-0.69%
SHAREHOLDERS EQUITY
Retained Earnings	$264.4M	$254.7M	$229.5M
YoY Change	10.55%	10.99%	16.22%
Common Stock	$466.0M	$467.2M	$462.7M
YoY Change	0.12%	0.98%	3.32%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$844.8M	$825.6M	$713.4M
YoY Change
Total Liabilities & Shareholders Equity	$6.748B	$6.563B	$5.616B
YoY Change	20.08%	16.87%	1.57%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2019 Q3
OPERATING ACTIVITIES
Net Income	$23.84M	$20.05M	$20.39M
YoY Change	15.0%	-1.66%	19.99%
Depreciation, Depletion And Amortization	$4.100M	$6.100M	$5.300M
YoY Change	-24.07%	15.09%	-17.19%
Cash From Operating Activities	$11.50M	$30.30M	$25.20M
YoY Change	-28.13%	20.24%	-17.38%
INVESTING ACTIVITIES
Capital Expenditures	-$500.0K	-$300.0K	-$1.100M
YoY Change	-66.67%	-72.73%	120.0%
Acquisitions
YoY Change
Other Investing Activities	$83.80M	-$211.6M	-$76.20M
YoY Change	-269.29%	177.69%	7.17%
Cash From Investing Activities	$83.30M	-$211.9M	-$77.30M
YoY Change	-263.33%	174.13%	7.81%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	127.5M	79.70M	49.20M
YoY Change	-1846.58%	61.99%	-175.34%
NET CHANGE
Cash From Operating Activities	11.50M	30.30M	25.20M
Cash From Investing Activities	83.30M	-211.9M	-77.30M
Cash From Financing Activities	127.5M	79.70M	49.20M
Net Change In Cash	222.3M	-101.9M	-2.900M
YoY Change	-625.53%	3413.79%	-97.28%
FREE CASH FLOW
Cash From Operating Activities	$11.50M	$30.30M	$25.20M
Capital Expenditures	-$500.0K	-$300.0K	-$1.100M
Free Cash Flow	$12.00M	$30.60M	$26.30M
YoY Change	-31.43%	16.35%	-15.16%

Facts In Submission

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	wabc	Contract Courier Expense ContractCourierExpense	1349000	USD
CY2020Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	72000	USD
CY2020Q3	wabc	Noninterest Expense Loss Contingency NoninterestExpenseLossContingency	0	USD
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	27027000
CY2019Q3	wabc	Noninterest Expense Loss Contingency NoninterestExpenseLossContingency	0	USD
	wabc	Noninterest Expense Loss Contingency NoninterestExpenseLossContingency	0	USD
	wabc	Noninterest Expense Loss Contingency NoninterestExpenseLossContingency	553000	USD
CY2020Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	3470000	USD
CY2019Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	2724000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	10341000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	9589000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	24603000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	24033000	USD
	us-gaap	Noninterest Expense NoninterestExpense	74021000	USD
	us-gaap	Noninterest Expense NoninterestExpense	74777000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	26772000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	27016000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	74909000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	78266000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6721000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6626000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18334000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18605000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	20051000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
	us-gaap	Net Income Loss NetIncomeLoss	56575000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26930000
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26986000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26977000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26924000
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26946000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26998000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26976000
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.10
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.22
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.74
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.10
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.21
CY2020Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.41
CY2019Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.41
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.23
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.22
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	20051000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
	us-gaap	Net Income Loss NetIncomeLoss	56575000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	14042000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	10407000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	110200000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	85822000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	4151000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	3077000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	32578000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	25372000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	713378000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	615591000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	60450000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	11177000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	1073000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	1484000	USD
	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	80000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	71000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	21000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	9891000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	7330000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	77572000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	60450000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	29942000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	27720000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	134147000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	120111000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	808076000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	20051000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	9891000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	450000	USD
CY2020Q3	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	19000	USD
CY2020Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	1868000	USD
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	11043000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	825576000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	731417000	USD
	us-gaap	Net Income Loss NetIncomeLoss	56575000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	77572000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	2838000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	534000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	1500000	USD
	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	85000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	11734000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	33263000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	825576000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	693437000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7330000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	2867000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	402000	USD
CY2019Q3	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	15000	USD
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	11063000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	488000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	32849000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	713378000	USD
	us-gaap	Net Income Loss NetIncomeLoss	56575000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	18482000	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	0	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	15178000	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	4300000	USD
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	2803000	USD
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	215000	USD
	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	1500000	USD
	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	1484000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	-0	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	433000	USD
	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	71000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	50000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	1982000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-323000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	4397000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2073000	USD
	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-520000	USD
	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-3386000	USD
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-325000	USD
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-6386000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	33000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	19000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	24798000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-12233000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	96240000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	64661000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	181894000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-73026000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1273000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1612633000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	732690000	USD
	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	0	USD
	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	1797000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	807064000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	502928000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	156993000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	184525000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1682000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2495000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	0	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	307000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-832152000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	28671000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	726569000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-70216000	USD
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	77045000	USD
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-5601000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2838000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	11177000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	11734000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	488000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	33263000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32849000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	761455000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-97977000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	25543000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-4645000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	373421000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	420284000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	398964000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	415639000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	6457000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	23587000	USD
	wabc	Right Of Use Asset Obtained In Exchange For Operating Lease Liability Amount Recognized Upon Adoption Of Asu201602 RightOfUseAssetObtainedInExchangeForOperatingLeaseLiabilityAmountRecognizedUponAdoptionOfASU201602	0	USD
	wabc	Right Of Use Asset Obtained In Exchange For Operating Lease Liability Amount Recognized Upon Adoption Of Asu201602 RightOfUseAssetObtainedInExchangeForOperatingLeaseLiabilityAmountRecognizedUponAdoptionOfASU201602	15325000	USD
	us-gaap	Other Significant Noncash Transaction Value Of Consideration Given1 OtherSignificantNoncashTransactionValueOfConsiderationGiven1	0	USD
	us-gaap	Other Significant Noncash Transaction Value Of Consideration Given1 OtherSignificantNoncashTransactionValueOfConsiderationGiven1	20114000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	4905000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	5123000	USD
	us-gaap	Interest Paid Net InterestPaidNet	1310000	USD
	us-gaap	Interest Paid Net InterestPaidNet	1417000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	18708000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	16021000	USD
CY2020Q1	wabc	Allowance For Credit Losses For Unfunded Commitments AllowanceForCreditLossesForUnfundedCommitments	19484000	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020Q1	wabc	Reserve For Unfunded Commitments ReserveForUnfundedCommitments	2160000	USD
CY2020Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	577811000	USD
	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	50000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	0	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3836879000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	148061000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	946000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3983994000	USD
CY2020Q3	wabc	Debt Securities Availableforsale And Heldtomaturity Amortized Cost DebtSecuritiesAvailableforsaleAndHeldtomaturityAmortizedCost	4414690000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	294698000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	295255000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	70378000	USD
CY2020Q3	wabc	Debt Securities Gross Unrecognized Gains DebtSecuritiesGrossUnrecognizedGains	164006000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	15945000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	39000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	593717000	USD
CY2020Q3	wabc	Debt Securities Gross Unrecognized Losses DebtSecuritiesGrossUnrecognizedLosses	985000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	4577711000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3041860000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	43857000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	6871000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3078846000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	738072000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	8460000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	2236000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	744296000	USD
CY2019Q4	wabc	Debt Securities Availableforsale And Heldtomaturity Amortized Cost DebtSecuritiesAvailableforsaleAndHeldtomaturityAmortizedCost	3779932000	USD
CY2019Q4	wabc	Debt Securities Gross Unrecognized Gains DebtSecuritiesGrossUnrecognizedGains	52317000	USD
CY2019Q4	wabc	Debt Securities Gross Unrecognized Losses DebtSecuritiesGrossUnrecognizedLosses	9107000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	3823142000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	452154000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	454493000	USD
CY2020Q3	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	63044000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	63504000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	973305000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1026667000	USD
CY2020Q3	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	132750000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	136640000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1480374000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1544476000	USD
CY2020Q3	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	107537000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	111448000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	207322000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	209476000	USD
CY2020Q3	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	0	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	0	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	3113155000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	3235112000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	303331000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	311592000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	723724000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	748882000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	274480000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	282125000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3836879000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3983994000	USD
CY2020Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	577811000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	593717000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	70602000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	1104775000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1122391000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	161911000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	165126000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	3	pure
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	18284000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	199000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	44	pure
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	340809000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	946000	USD
CY2020Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	850245000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	760365000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	670595000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	683277000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	149492000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	153724000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	33489000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	34465000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	0	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	0	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	2103557000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	2135388000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	381781000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	389452000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	938303000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	943458000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	356291000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	354844000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3041860000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3078846000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	738072000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	744296000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	41	pure
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	322525000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	747000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	16	pure
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	96910000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	314000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	70	pure
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	462348000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	6557000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	86	pure
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	559258000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	6871000	USD
CY2019Q4	wabc	Heldtomaturity Securities Less Than12 Months Number Of Positions HeldtomaturitySecuritiesLessThan12MonthsNumberOfPositions	6	pure
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	12098000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	87000	USD
CY2019Q4	wabc	Heldtomaturity Securities12 Months Or Longer Number Of Positions HeldtomaturitySecurities12MonthsOrLongerNumberOfPositions	55	pure
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	277454000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	2149000	USD
CY2019Q4	wabc	Heldtomaturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 HeldtomaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	61	pure
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	289552000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	2236000	USD
CY2020Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	577811000	USD
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
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	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityAllowanceForCreditLossWriteoff	0	USD
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CY2020Q3	us-gaap	Debt Securities Held To Maturity Nonaccrual DebtSecuritiesHeldToMaturityNonaccrual	0	USD
CY2020Q3	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	23079000	USD
CY2019Q3	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	19586000	USD
	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	67963000	USD
	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	56992000	USD
CY2020Q3	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	2911000	USD
CY2019Q3	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	3777000	USD
	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	9501000	USD
	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	12165000	USD
CY2020Q3	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	25990000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	23363000	USD
	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	77464000	USD
	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	69157000	USD
CY2020Q3	us-gaap	Notes Receivable Gross NotesReceivableGross	1310009000	USD
CY2020Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	0	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	872000	USD
CY2020Q3	us-gaap	Notes Receivable Gross NotesReceivableGross	1310009000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1126664000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1126664000	USD
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	24529000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	485000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	24142000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	19484000	USD
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	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	3249000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1590000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	24142000	USD
CY2019Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	20117000	USD
CY2019Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	0	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	1039000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	750000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	19828000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	21351000	USD
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	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	3403000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1880000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	19828000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	2413000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	17071000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	19484000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	15824000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	1110840000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1126664000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	1300985000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	4380000	USD
CY2020Q3	us-gaap	Notes Receivable Gross NotesReceivableGross	1310009000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	1114951000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	4440000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1126664000	USD
CY2020Q3	wabc	Loans And Leases Receivable Nonaccrual Commitment To Lend LoansAndLeasesReceivableNonaccrualCommitmentToLend	0	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	7662000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	9140000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	8160000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	8160000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2413000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	15822000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	17300000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2413000	USD
CY2019Q3	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	16962000	USD
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CY2020Q3	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	6304000	USD
CY2020Q3	wabc	Financing Receivable Modifications Period End Impairment Allowance FinancingReceivableModificationsPeriodEndImpairmentAllowance	0	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	9	pure
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CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	6713000	USD
CY2019Q4	wabc	Financing Receivable Modifications Period End Impairment Allowance FinancingReceivableModificationsPeriodEndImpairmentAllowance	11000	USD
CY2020Q3	us-gaap	Financing Receivables Impaired Troubled Debt Restructuring Write Down FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown	0	USD
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CY2020Q3	us-gaap	Other Real Estate OtherRealEstate	43000	USD
CY2020Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	410000	USD
CY2019Q4	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	124000	USD
CY2020Q3	wabc	Unsecured Loan Limit Percentage Of Shareholders Equity California Financial Code UnsecuredLoanLimitPercentageOfShareholdersEquityCaliforniaFinancialCode	0.15	pure
CY2020Q3	wabc	Secured And Unsecured Loan Limit Percentage California Financial Code SecuredAndUnsecuredLoanLimitPercentageCaliforniaFinancialCode	0.25	pure
CY2020Q3	wabc	Loan Commitments And Standby Letters Of Credit Related To Real Estate Loans LoanCommitmentsAndStandbyLettersOfCreditRelatedToRealEstateLoans	39779000	USD
CY2019Q4	wabc	Loan Commitments And Standby Letters Of Credit Related To Real Estate Loans LoanCommitmentsAndStandbyLettersOfCreditRelatedToRealEstateLoans	43129000	USD
CY2020Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	19098000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	17136000	USD
CY2020Q3	wabc	Lihtc Investments LIHTCInvestments	18935000	USD
CY2019Q4	wabc	Lihtc Investments LIHTCInvestments	20773000	USD
CY2020Q3	us-gaap	Interest Receivable Current InterestReceivableCurrent	30779000	USD
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CY2020Q3	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	3619000	USD
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CY2020Q3	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	13743000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	10767000	USD
CY2020Q3	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	14069000	USD
CY2019Q4	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	14069000	USD
CY2020Q3	us-gaap	Other Investments And Securities At Cost OtherInvestmentsAndSecuritiesAtCost	158000	USD
CY2019Q4	us-gaap	Other Investments And Securities At Cost OtherInvestmentsAndSecuritiesAtCost	158000	USD
CY2020Q3	us-gaap	Cost Method Investments CostMethodInvestments	14227000	USD
CY2019Q4	us-gaap	Cost Method Investments CostMethodInvestments	14227000	USD
CY2020Q3	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	59868000	USD
CY2019Q4	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	57810000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	11085000	USD
CY2020Q3	us-gaap	Other Assets OtherAssets	160269000	USD
CY2019Q4	us-gaap	Other Assets OtherAssets	164332000	USD
CY2020Q3	wabc	Lihtc Investments LIHTCInvestments	18935000	USD
CY2020Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	13397000	USD
CY2019Q4	wabc	Lihtc Investments LIHTCInvestments	20773000	USD
CY2019Q4	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	16231000	USD
CY2020Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	13397000	USD
CY2020Q3	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	640000	USD
CY2019Q3	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	600000	USD
	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	1840000	USD
	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	1800000	USD
CY2020Q3	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	225000	USD
CY2019Q3	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	225000	USD
	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	675000	USD
	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	675000	USD
CY2020Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	21819000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	0	USD
CY2020Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	19098000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	17136000	USD
CY2020Q3	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	49559000	USD
CY2019Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	27453000	USD
CY2020Q3	us-gaap	Other Liabilities OtherLiabilities	90476000	USD
CY2019Q4	us-gaap	Other Liabilities OtherLiabilities	44589000	USD
CY2020Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	21819000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-21942000	USD
CY2020Q3	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	43492000	USD
	us-gaap	Debt Securities Available For Sale Unrealized Gain Loss DebtSecuritiesAvailableForSaleUnrealizedGainLoss	147115000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	11085000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	10934000	USD
CY2020Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	19098000	USD
CY2020Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	19098000	USD
CY2020Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P4Y9M18D
CY2020Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0225	pure
CY2020Q3	us-gaap	Operating Lease Cost OperatingLeaseCost	1671000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	4988000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	1599000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	5353000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4426000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	3689000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	2078000	USD
CY2020Q3	wabc	Lessee Operating Lease Liability To Be Paid After Year Four LesseeOperatingLeaseLiabilityToBePaidAfterYearFour	2863000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	20008000	USD
CY2020Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	910000	USD
CY2020Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	19098000	USD
CY2020Q3	wabc	Amortization Expense Adjustment Resulting From A Change In Estimates Of Useful Lives Or Residual Values AmortizationExpenseAdjustmentResultingFromAChangeInEstimatesOfUsefulLivesOrResidualValues	0	USD
CY2020Q3	us-gaap	Goodwill Goodwill	121673000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	121673000	USD
CY2019Q4	us-gaap	Carrying Value Of Securities Sold Under Repurchase Agreements And Deposits Received For Securities Loaned CarryingValueOfSecuritiesSoldUnderRepurchaseAgreementsAndDepositsReceivedForSecuritiesLoaned	264571000	USD
CY2020Q3	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	2684028000	USD
CY2019Q4	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	2240112000	USD
CY2020Q3	us-gaap	Demand Deposit Accounts DemandDepositAccounts	1040712000	USD
CY2019Q4	us-gaap	Demand Deposit Accounts DemandDepositAccounts	931888000	USD
CY2020Q3	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	1653000000	USD
CY2019Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	1471284000	USD
CY2020Q3	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	83838000	USD
CY2019Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	88355000	USD
CY2020Q3	wabc	Time Deposits100 Thousand Through250 Thousand TimeDeposits100ThousandThrough250Thousand	50378000	USD
CY2019Q4	wabc	Time Deposits100 Thousand Through250 Thousand TimeDeposits100ThousandThrough250Thousand	54874000	USD
CY2020Q3	wabc	Time Deposits More Than250 Thousand TimeDepositsMoreThan250Thousand	27234000	USD
CY2019Q4	wabc	Time Deposits More Than250 Thousand TimeDepositsMoreThan250Thousand	26108000	USD
CY2020Q3	us-gaap	Deposits Deposits	5539190000	USD
CY2019Q4	us-gaap	Deposits Deposits	4812621000	USD
CY2020Q3	wabc	Demand Deposit Overdrafts DemandDepositOverdrafts	1466000	USD
CY2019Q4	wabc	Demand Deposit Overdrafts DemandDepositOverdrafts	1055000	USD
CY2020Q3	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	80000	USD
	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	238000	USD
CY2019Q3	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	81000	USD
	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	246000	USD
	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<table cellpadding="0" cellspacing="0" class="finTable" style="width: 100%; font-size: 10pt; font-family: "Times New Roman", Times, serif; text-indent: 0px; margin-left: 0pt; margin-right: 0pt;"><tbody><tr style="vertical-align: bottom; font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="6" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0); width: 22%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">Repurchase Agreements (Sweep)<br/> Accounted for as Secured Borrowings</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid rgb(0, 0, 0); width: 1%;"> </td></tr> <tr style="vertical-align: bottom; font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="border-bottom: 1px none rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> </td><td style="border-bottom: 1px none rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="6" style="border-bottom: 1px none rgb(0, 0, 0); text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; width: 22%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">Remaining Contractual Maturity of the Agreements</p> </td><td style="border-bottom: 1px none rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td></tr> <tr style="vertical-align: bottom; font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="6" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0); width: 22%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">Overnight and Continuous</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid rgb(0, 0, 0); width: 1%;"> </td></tr> <tr style="vertical-align: bottom; font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; width: 1%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">At September 30,</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; width: 1%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">At December 31,</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td></tr> <tr style="vertical-align: bottom; font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0); width: 1%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">2020</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid rgb(0, 0, 0); width: 1%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0); width: 1%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">2019</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid rgb(0, 0, 0); width: 1%;"> </td></tr> <tr style="vertical-align: bottom; font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Repurchase agreements:</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td colspan="6" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; width: 22%;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;"><em style="font: inherit;"><em style="font: inherit;">(In thousands)</em></em></p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255); font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt; margin-left: 9pt;">Collateral securing borrowings:</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td style="text-align: left; font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 18%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td><td style="text-align: left; font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 18%;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 1%;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255); font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt; margin-left: 18pt;">Securities of U.S. Government sponsored entities</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">-</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">65,833</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255); font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt; margin-left: 18pt;">Agency residential MBS</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">76,715</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">52,485</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255); font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt; margin-left: 18pt;">Corporate securities</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid black;"> </td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid black;">183,447</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid black;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid black;"> </td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid black;">146,253</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid black;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255); font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt; margin-left: 27pt;">Total collateral carrying value</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">$</td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">260,162</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 3px double rgb(0, 0, 0); margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">$</td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">264,571</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 3px double rgb(0, 0, 0); margin-left: 0pt;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255); font-family: "Times New Roman", Times, serif; font-size: 10pt;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 58%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Total short-term borrowed funds</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">107,973</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 18%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">30,928</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td></tr> </tbody></table>
CY2020Q3	us-gaap	Carrying Value Of Securities Sold Under Repurchase Agreements And Deposits Received For Securities Loaned CarryingValueOfSecuritiesSoldUnderRepurchaseAgreementsAndDepositsReceivedForSecuritiesLoaned	260162000	USD
CY2020Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	16000
CY2020Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	107973000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	30928000	USD
CY2020Q3	wabc	Loan Commitments Not Unconditionally Cancellable LoanCommitmentsNotUnconditionallyCancellable	39779000	USD
CY2020Q3	wabc	Unfunded Loan Commitments UnfundedLoanCommitments	279330000	USD
CY2019Q4	wabc	Unfunded Loan Commitments UnfundedLoanCommitments	265311000	USD
CY2020Q3	us-gaap	Guarantee Obligations Current Carrying Value GuaranteeObligationsCurrentCarryingValue	580000	USD
CY2019Q4	us-gaap	Guarantee Obligations Current Carrying Value GuaranteeObligationsCurrentCarryingValue	550000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	20051000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
	us-gaap	Net Income Loss NetIncomeLoss	56575000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26930000
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26986000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26977000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26924000
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.10
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.22
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26930000
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26986000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26977000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26924000
CY2019Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	41000
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	21000
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	52000
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26946000
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	27027000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26998000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26976000
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.74
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.10
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.21

Files In Submission

Name	View Source	Status
0001171843-20-007649-index-headers.html	Edgar Link	pending
0001171843-20-007649-index.html	Edgar Link	pending
0001171843-20-007649.txt	Edgar Link	pending
0001171843-20-007649-xbrl.zip	Edgar Link	pending
ex_210491.htm	Edgar Link	pending
ex_210492.htm	Edgar Link	pending
ex_210493.htm	Edgar Link	pending
ex_210494.htm	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending
wabc-20200930.xsd	Edgar Link	pending
wabc-20200930_cal.xml	Edgar Link	unprocessable
wabc-20200930_def.xml	Edgar Link	unprocessable
wabc-20200930_lab.xml	Edgar Link	unprocessable
wabc-20200930_pre.xml	Edgar Link	unprocessable
wabc20200930_10q.htm	Edgar Link	pending
wabc20200930_10q_htm.xml	Edgar Link	completed

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$WABC
Westamerica Bancorp Stock $wabc

2020 Q4 Form 10-Q Financial Statement

#000117184320007649 Filed on November 05, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WABC Westamerica Bancorp Stock $wabc

2020 Q4 Form 10-Q Financial Statement

#000117184320007649 Filed on November 05, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WABC
Westamerica Bancorp Stock $wabc