$WABC
Westamerica Bancorp Stock $wabc

$wabc Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-Q Financial Statement

#000117184319007133 Filed on November 04, 2019

Income Statement

Concept	2019 Q4	2019 Q3	2018 Q3
Revenue	$39.88M	$39.70M	$38.61M
YoY Change	1.09%	2.8%	11.53%
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	$5.400M	$5.300M	$6.400M
YoY Change	0.0%	-17.19%	-4.48%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$455.0K	$527.0K
YoY Change		-13.66%	11.42%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$26.95M	$27.02M	$21.25M
YoY Change	7.61%	27.14%	0.68%
Income Tax	$6.200M	$6.626M	$4.256M
% Of Pretax Income	23.01%	24.53%	20.03%
Net Earnings	$20.73M	$20.39M	$16.99M
YoY Change	8.78%	19.99%	13.16%
Net Earnings / Revenue	51.98%	51.37%	44.01%
Basic Earnings Per Share	$0.77	$0.76	$0.64
Diluted Earnings Per Share	$0.77	$0.75	$0.63
COMMON SHARES
Basic Shares Outstanding	27.06M	26.99M	26.70M
Diluted Shares Outstanding		27.03M	26.82M

Balance Sheet

Concept	2019 Q4	2019 Q3	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$373.4M	$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	$34.60M	$34.08M	$35.39M
YoY Change	0.26%	-3.7%	-0.33%
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	$11.10M	$11.90M	$48.60M
YoY Change	-73.76%	-75.51%	-1.82%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$5.620B	$5.616B	$5.529B
YoY Change	0.92%	1.57%	1.54%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$17.10M	$19.70M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$30.93M	$45.65M	$61.76M
YoY Change	-39.65%	-26.09%	-6.91%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$17.10M	$19.70M	$61.80M
YoY Change	-66.6%	-68.12%	-6.79%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$27.50M	$40.70M	$39.30M
YoY Change	-20.98%	3.56%	-3.91%
Total Long-Term Liabilities	$27.50M	$40.70M	$39.30M
YoY Change	-20.98%	3.56%	-3.91%
TOTAL LIABILITIES
Total Short-Term Liabilities	$17.10M	$19.70M	$61.80M
Total Long-Term Liabilities	$27.50M	$40.70M	$39.30M
Total Liabilities	$4.888B	$4.903B	$4.937B
YoY Change	-1.31%	-0.69%	1.96%
SHAREHOLDERS EQUITY
Retained Earnings	$239.1M	$229.5M	$197.5M
YoY Change	16.17%	16.22%	9.59%
Common Stock	$465.5M	$462.7M	$447.8M
YoY Change	3.82%	3.32%	5.2%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$731.4M	$713.4M	$592.6M
YoY Change
Total Liabilities & Shareholders Equity	$5.620B	$5.616B	$5.529B
YoY Change	0.92%	1.57%	1.54%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2018 Q3
OPERATING ACTIVITIES
Net Income	$20.73M	$20.39M	$16.99M
YoY Change	8.78%	19.99%	13.16%
Depreciation, Depletion And Amortization	$5.400M	$5.300M	$6.400M
YoY Change	0.0%	-17.19%	-4.48%
Cash From Operating Activities	$16.00M	$25.20M	$30.50M
YoY Change	-1.23%	-17.38%	23.48%
INVESTING ACTIVITIES
Capital Expenditures	-$1.500M	-$1.100M	-$500.0K
YoY Change	400.0%	120.0%	-44.44%
Acquisitions
YoY Change
Other Investing Activities	-$49.50M	-$76.20M	-$71.10M
YoY Change	-61.39%	7.17%	191.39%
Cash From Investing Activities	-$51.00M	-$77.30M	-$71.70M
YoY Change	-60.31%	7.81%	183.4%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-7.300M	49.20M	-65.30M
YoY Change	-173.74%	-175.34%	-297.88%
NET CHANGE
Cash From Operating Activities	16.00M	25.20M	30.50M
Cash From Investing Activities	-51.00M	-77.30M	-71.70M
Cash From Financing Activities	-7.300M	49.20M	-65.30M
Net Change In Cash	-42.30M	-2.900M	-106.5M
YoY Change	-58.69%	-97.28%	-428.7%
FREE CASH FLOW
Cash From Operating Activities	$16.00M	$25.20M	$30.50M
Capital Expenditures	-$1.500M	-$1.100M	-$500.0K
Free Cash Flow	$17.50M	$26.30M	$31.00M
YoY Change	6.06%	-15.16%	21.09%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	27016000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	21249000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	78266000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	65953000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4256000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18605000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6626000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13444000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	16993000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52509000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26986000
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26701000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26924000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26622000
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	27027000
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26815000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26976000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26736000
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.64
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.22
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.97
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.21
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.96
CY2019Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.41
CY2018Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.40
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.22
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.20
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	16993000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52509000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	10407000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-5915000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	85822000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-47915000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	3077000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-1749000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	25372000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-14164000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	7330000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-4166000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	60450000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-33751000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	27720000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	12827000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	120111000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	18758000	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
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	713378000	USD
CY2018Q2	us-gaap	Stockholders Equity StockholdersEquity	586138000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	16993000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-4166000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	3762000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	525000	USD
	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	1484000	USD
	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	1575000	USD
CY2018Q3	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	22000	USD
CY2018Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10683000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	592591000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	615591000	USD
CY2018Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	-2801000	USD
CY2018Q4	wabc	Stockholders Equity Adjusted Balance StockholdersEquityAdjustedBalance	612790000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	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
	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
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	590239000	USD
CY2017Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	0	USD
CY2017Q4	wabc	Stockholders Equity Adjusted Balance StockholdersEquityAdjustedBalance	590239000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52509000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-33751000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	13245000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	1143000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	1575000	USD
	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	99000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	524000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	31944000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	592591000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52509000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	15178000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	18964000	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	0	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	0	USD
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	215000	USD
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	181000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-323000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	177000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2073000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	1896000	USD
	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	3386000	USD
	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-7760000	USD
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-6386000	USD
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	1345000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	19000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	5000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-12233000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	3793000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	433000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	585000	USD
	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	50000	USD
	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	-66000	USD
	wabc	Net Writedown Of Premises And Equipment NetWritedownOfPremisesAndEquipment	-0	USD
	wabc	Net Writedown Of Premises And Equipment NetWritedownOfPremisesAndEquipment	-3000	USD
	wabc	Gain Loss On Sale Of Foreclosed Assets GainLossOnSaleOfForeclosedAssets	-0	USD
	wabc	Gain Loss On Sale Of Foreclosed Assets GainLossOnSaleOfForeclosedAssets	94000	USD
	wabc	Impairment Of Foreclosed Assets ImpairmentOfForeclosedAssets	0	USD
	wabc	Impairment Of Foreclosed Assets ImpairmentOfForeclosedAssets	27000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	64661000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-91594000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	80424000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-73026000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1273000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1183000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	732690000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	634113000	USD
	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	1797000	USD
	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	0	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 Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	290663000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	184525000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	127578000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2495000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2830000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	307000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	873000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	28671000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-125052000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-70216000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	8224000	USD
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-5601000	USD
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	3285000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	11177000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	13245000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	488000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	524000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32849000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	31944000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-97977000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-7714000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-4645000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-52342000	USD
CY2018Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	420284000	USD
CY2017Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	575002000	USD
CY2019Q3	us-gaap	Cash And Due From Banks CashAndDueFromBanks	415639000	USD
CY2018Q3	us-gaap	Cash And Due From Banks CashAndDueFromBanks	522660000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	23587000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
	wabc	Right Of Use Asset Obtained In Exchange For Operating Lease Liability Amount Recognized Upon Adoption Of Asu201602 RightOfUseAssetObtainedInExchangeForOperatingLeaseLiabilityAmountRecognizedUponAdoptionOfASU201602	15325000	USD
	wabc	Right Of Use Asset Obtained In Exchange For Operating Lease Liability Amount Recognized Upon Adoption Of Asu201602 RightOfUseAssetObtainedInExchangeForOperatingLeaseLiabilityAmountRecognizedUponAdoptionOfASU201602	0	USD
	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	0	USD
	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	0	USD
	us-gaap	Other Significant Noncash Transaction Value Of Consideration Given1 OtherSignificantNoncashTransactionValueOfConsiderationGiven1	20114000	USD
	us-gaap	Other Significant Noncash Transaction Value Of Consideration Given1 OtherSignificantNoncashTransactionValueOfConsiderationGiven1	0	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	5123000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	0	USD
	us-gaap	Interest Paid Net InterestPaidNet	1417000	USD
	us-gaap	Interest Paid Net InterestPaidNet	1440000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	16021000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	7028000	USD
CY2018Q1	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	1800000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	1747000	USD
	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	50000	USD
	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	-66000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2954728000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	38855000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	9816000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2983767000	USD
CY2019Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	793216000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	8683000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	2658000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	799241000	USD
CY2019Q3	wabc	Debt Securities Availableforsale And Heldtomaturity Amortized Cost DebtSecuritiesAvailableforsaleAndHeldtomaturityAmortizedCost	3747944000	USD
CY2019Q3	wabc	Debt Securities Gross Unrecognized Gains DebtSecuritiesGrossUnrecognizedGains	47538000	USD
CY2019Q3	wabc	Debt Securities Gross Unrecognized Losses DebtSecuritiesGrossUnrecognizedLosses	12474000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	3783008000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2711453000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	3597000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	60380000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2654670000	USD
CY2018Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	984609000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	3692000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	16856000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	971445000	USD
CY2018Q4	wabc	Debt Securities Availableforsale And Heldtomaturity Amortized Cost DebtSecuritiesAvailableforsaleAndHeldtomaturityAmortizedCost	3696062000	USD
CY2018Q4	wabc	Debt Securities Gross Unrecognized Gains DebtSecuritiesGrossUnrecognizedGains	7289000	USD
CY2018Q4	wabc	Debt Securities Gross Unrecognized Losses DebtSecuritiesGrossUnrecognizedLosses	77236000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	3626115000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	284550000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	285060000	USD
CY2019Q3	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	64092000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	64247000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	1182895000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1199153000	USD
CY2019Q3	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	179576000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	182635000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	471434000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	478841000	USD
CY2019Q3	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	169082000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	173661000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	35934000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	37107000	USD
CY2019Q3	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	0	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	0	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	1974813000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	2000161000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	412750000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	420543000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	979915000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2954728000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2983767000	USD
CY2019Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	793216000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	983606000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	380466000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	378698000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	799241000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	262418000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	261976000	USD
CY2018Q4	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	86172000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	86148000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	1438849000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1414020000	USD
CY2018Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	214137000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	213829000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	85817000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	85877000	USD
CY2018Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	232544000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	233515000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	38672000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	36970000	USD
CY2018Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	1037000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	1074000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	1825756000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	1798843000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	533890000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	534566000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	885697000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	855827000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	450719000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	436879000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2711453000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2654670000	USD
CY2018Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	984609000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	971445000	USD
CY2018Q4	wabc	High Risk Collateralized Mortgage Obligations HighRiskCollateralizedMortgageObligations	0	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	19	pure
CY2019Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	169787000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1288000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	85	pure
CY2019Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	628586000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	8528000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	104	pure
CY2019Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	798373000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	9816000	USD
CY2019Q3	wabc	Heldtomaturity Securities Less Than12 Months Number Of Positions HeldtomaturitySecuritiesLessThan12MonthsNumberOfPositions	7	pure
CY2019Q3	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	13020000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	90000	USD
CY2019Q3	wabc	Heldtomaturity Securities12 Months Or Longer Number Of Positions HeldtomaturitySecurities12MonthsOrLongerNumberOfPositions	66	pure
CY2019Q3	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	315290000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	2568000	USD
CY2019Q3	wabc	Heldtomaturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 HeldtomaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	73	pure
CY2019Q3	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	328310000	USD
CY2019Q3	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	2658000	USD
CY2019Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	721741000	USD
CY2018Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	728161000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	82	pure
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	499743000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	4111000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	2048896000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	301	pure
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	219	pure
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1549153000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	56269000	USD
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CY2018Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	60380000	USD
CY2018Q4	wabc	Heldtomaturity Securities Less Than12 Months Number Of Positions HeldtomaturitySecuritiesLessThan12MonthsNumberOfPositions	114	pure
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	92154000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	305000	USD
CY2018Q4	wabc	Heldtomaturity Securities12 Months Or Longer Number Of Positions HeldtomaturitySecurities12MonthsOrLongerNumberOfPositions	220	pure
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	564120000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	16551000	USD
CY2018Q4	wabc	Heldtomaturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 HeldtomaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	334	pure
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	656274000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	16856000	USD
CY2019Q3	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	19586000	USD
CY2018Q3	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	16780000	USD
	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	56992000	USD
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CY2019Q3	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	3777000	USD
CY2018Q3	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	4880000	USD
	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	12165000	USD
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CY2019Q3	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	23363000	USD
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CY2018Q4	us-gaap	Fdic Indemnification Asset FDICIndemnificationAsset	5713000	USD
CY2018Q4	wabc	Percent Of Principal Covered By Fdic PercentOfPrincipalCoveredByFDIC	0.80	pure
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CY2018Q4	wabc	Loans And Leases Receivable Gross Carrying Amount Covered And Noncovered LoansAndLeasesReceivableGrossCarryingAmountCoveredAndNoncovered	1207202000	USD
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CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	750000	USD
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CY2019Q3	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	18474000	USD
CY2019Q3	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2550000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	19369000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	21445000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2752000	USD
CY2019Q3	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	16962000	USD
CY2019Q3	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	208000	USD
CY2018Q3	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	22084000	USD
CY2018Q3	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	372000	USD
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	16836000	USD
	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	819000	USD
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	23428000	USD
	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	1132000	USD
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	10	pure
	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	9398000	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	6754000	USD
CY2019Q3	wabc	Financing Receivable Modifications Period End Impairment Allowance FinancingReceivableModificationsPeriodEndImpairmentAllowance	18000	USD
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	13	pure
CY2018	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	11752000	USD
CY2018Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	8579000	USD
CY2018Q4	wabc	Financing Receivable Modifications Period End Impairment Allowance FinancingReceivableModificationsPeriodEndImpairmentAllowance	19000	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	pure
CY2018Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged As Collateral PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedAsCollateral	0	USD
CY2019Q3	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	0	USD
CY2019Q3	us-gaap	Other Real Estate OtherRealEstate	43000	USD
CY2019Q3	wabc	Other Real Estate Reserve OtherRealEstateReserve	0	USD
CY2018Q4	us-gaap	Other Real Estate OtherRealEstate	350000	USD
CY2018Q4	wabc	Other Real Estate Reserve OtherRealEstateReserve	0	USD
CY2018Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	0	USD
CY2019Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	114000	USD
CY2018Q4	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	516000	USD
CY2019Q3	wabc	Unsecured Loan Limit Percentage Of Shareholders Equity California Financial Code UnsecuredLoanLimitPercentageOfShareholdersEquityCaliforniaFinancialCode	0.15	pure
CY2019Q3	wabc	Secured And Unsecured Loan Limit Percentage California Financial Code SecuredAndUnsecuredLoanLimitPercentageCaliforniaFinancialCode	0.25	pure
CY2019Q3	wabc	Loan Commitments And Standby Letters Of Credit Related To Real Estate Loans LoanCommitmentsAndStandbyLettersOfCreditRelatedToRealEstateLoans	44964000	USD
CY2018Q4	wabc	Loan Commitments And Standby Letters Of Credit Related To Real Estate Loans LoanCommitmentsAndStandbyLettersOfCreditRelatedToRealEstateLoans	53891000	USD
CY2019Q3	wabc	Concentration Risk Issuer Relationships ConcentrationRiskIssuerRelationships	88	pure
CY2019Q3	wabc	Concentration Risk Aggregate Securities Amount ConcentrationRiskAggregateSecuritiesAmount	5000000	USD
CY2018Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	0	USD
CY2019Q3	wabc	Lihtc Investments LIHTCInvestments	8143000	USD
CY2019Q3	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	14069000	USD
CY2018Q4	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	14069000	USD
CY2019Q3	us-gaap	Other Investments And Securities At Cost OtherInvestmentsAndSecuritiesAtCost	158000	USD
CY2018Q4	us-gaap	Other Investments And Securities At Cost OtherInvestmentsAndSecuritiesAtCost	158000	USD
CY2019Q3	us-gaap	Cost Method Investments CostMethodInvestments	14227000	USD
CY2018Q4	us-gaap	Cost Method Investments CostMethodInvestments	14227000	USD
CY2019Q3	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	57169000	USD
CY2018Q4	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	56083000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	11947000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	42256000	USD
CY2019Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	19721000	USD
CY2018Q4	wabc	Lihtc Investments LIHTCInvestments	10219000	USD
CY2019Q3	us-gaap	Interest Receivable Current InterestReceivableCurrent	25511000	USD
CY2018Q4	us-gaap	Interest Receivable Current InterestReceivableCurrent	25834000	USD
CY2019Q3	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	3530000	USD
CY2018Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	4658000	USD
CY2019Q3	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	12524000	USD
CY2018Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	9629000	USD
CY2019Q3	us-gaap	Other Assets OtherAssets	152772000	USD
CY2018Q4	us-gaap	Other Assets OtherAssets	162906000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	11947000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	8585000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	42256000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	16787000	USD
CY2019Q3	wabc	Lihtc Investments LIHTCInvestments	8143000	USD
CY2019Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	4754000	USD
CY2018Q4	wabc	Lihtc Investments LIHTCInvestments	10219000	USD
CY2018Q4	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	4799000	USD
CY2019Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	4754000	USD
CY2019Q3	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	600000	USD
CY2018Q3	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	900000	USD
	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	1800000	USD
	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	2200000	USD
CY2019Q3	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	225000	USD
CY2018Q3	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	336000	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	1008000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	19721000	USD
CY2018Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	0	USD
CY2019Q3	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	40687000	USD
CY2018Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	34849000	USD
CY2019Q3	us-gaap	Other Liabilities OtherLiabilities	60408000	USD
CY2018Q4	us-gaap	Other Liabilities OtherLiabilities	34849000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Term Of Contract LesseeOperatingLeaseTermOfContract	P5Y
CY2019Q3	us-gaap	Lessee Operating Lease Renewal Term LesseeOperatingLeaseRenewalTerm	P5Y
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	19721000	USD
CY2019Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	19721000	USD
CY2019Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P3Y9M25D
CY2019Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0293	pure
CY2019Q3	us-gaap	Operating Lease Cost OperatingLeaseCost	1726000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	5145000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	2719000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	6283000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	4574000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	3632000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2912000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	2057000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	22177000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	2456000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	19721000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	5996000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	4409000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	2741000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	1921000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	1223000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	1044000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	17334000	USD
CY2019Q3	wabc	Amortization Expense Adjustment Resulting From A Change In Estimates Of Useful Lives Or Residual Values AmortizationExpenseAdjustmentResultingFromAChangeInEstimatesOfUsefulLivesOrResidualValues	0	USD
CY2019Q3	us-gaap	Goodwill Goodwill	121673000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	121673000	USD
CY2019Q3	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	2265640000	USD
CY2018Q4	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	2243251000	USD
CY2019Q3	us-gaap	Demand Deposit Accounts DemandDepositAccounts	910566000	USD
CY2018Q4	us-gaap	Demand Deposit Accounts DemandDepositAccounts	929346000	USD
CY2019Q3	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	1445210000	USD
CY2018Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	1498991000	USD
CY2019Q3	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	92300000	USD
CY2018Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	102654000	USD
CY2019Q3	wabc	Time Deposits100 Thousand Through250 Thousand TimeDeposits100ThousandThrough250Thousand	56066000	USD
CY2018Q4	wabc	Time Deposits100 Thousand Through250 Thousand TimeDeposits100ThousandThrough250Thousand	64512000	USD
CY2019Q3	wabc	Time Deposits More Than250 Thousand TimeDepositsMoreThan250Thousand	26841000	USD
CY2018Q4	wabc	Time Deposits More Than250 Thousand TimeDepositsMoreThan250Thousand	28085000	USD
CY2019Q3	us-gaap	Deposits Deposits	4796623000	USD
CY2018Q4	us-gaap	Deposits Deposits	4866839000	USD
CY2019Q3	wabc	Demand Deposit Overdrafts DemandDepositOverdrafts	1078000	USD
CY2018Q4	wabc	Demand Deposit Overdrafts DemandDepositOverdrafts	980000	USD
CY2019Q3	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	81000	USD
	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	246000	USD
CY2018Q3	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	91000	USD
	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	283000	USD
	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<table border="0" cellpadding="0" cellspacing="0" class="finTable" style="margin-right: 10%; width: 90%; font-size: 10pt; font-family: "Times New Roman", Times, serif; text-indent: 0px;"> <tbody> <tr style="vertical-align: bottom;"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </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);"> <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);"> </td> </tr> <tr style="vertical-align: bottom;"> <td style="border-bottom: 1px rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="border-bottom: 1px rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td colspan="6" style="border-bottom: 1px rgb(0, 0, 0); text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <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 rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> </tr> <tr style="vertical-align: bottom;"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </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);"> <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);"> </td> </tr> <tr style="vertical-align: bottom;"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <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;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <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;"> </td> </tr> <tr style="vertical-align: bottom;"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </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);"> <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);"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </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);"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">2018</p> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 1px solid rgb(0, 0, 0);"> </td> </tr> <tr style="vertical-align: bottom;"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 66%;"> <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;"> </td> <td colspan="6" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;"><em style="font-weight: inherit; font-style: normal;"><em style="font-weight: inherit; font-style: normal;">(In thousands)</em></em></p> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <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;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="text-align: left; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="text-align: left; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <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;">$</td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">75,784</td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">73,803</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);"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <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: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">55,013</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: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">58,380</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);"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <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: thin solid rgb(0, 0, 0);"> </td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: thin solid rgb(0, 0, 0);">115,018</td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: thin solid rgb(0, 0, 0);"> </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: thin solid rgb(0, 0, 0);"> </td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: thin solid rgb(0, 0, 0);">91,837</td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: thin solid rgb(0, 0, 0);"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <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);">$</td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">245,815</td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 3px double rgb(0, 0, 0); margin-left: 0pt;"> </td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">$</td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">224,020</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);"> <td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <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; border-bottom: 3px double rgb(0, 0, 0);">$</td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">45,646</td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; border-bottom: 3px double rgb(0, 0, 0); margin-left: 0pt;"> </td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">$</td> <td style="width: 14%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 3px double rgb(0, 0, 0);">51,247</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> </tbody> </table>
CY2019Q3	us-gaap	Carrying Value Of Securities Sold Under Repurchase Agreements And Deposits Received For Securities Loaned CarryingValueOfSecuritiesSoldUnderRepurchaseAgreementsAndDepositsReceivedForSecuritiesLoaned	245815000	USD
CY2018Q4	us-gaap	Carrying Value Of Securities Sold Under Repurchase Agreements And Deposits Received For Securities Loaned CarryingValueOfSecuritiesSoldUnderRepurchaseAgreementsAndDepositsReceivedForSecuritiesLoaned	224020000	USD
CY2019Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	45646000	USD
CY2018Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	51247000	USD
	wabc	Securities Selected For Otti Analysis Market Price Threshold SecuritiesSelectedForOTTIAnalysisMarketPriceThreshold	0.95	pure
CY2019Q3	wabc	Unfunded Loan Commitments UnfundedLoanCommitments	286876000	USD
CY2018Q4	wabc	Unfunded Loan Commitments UnfundedLoanCommitments	278598000	USD
CY2019Q3	us-gaap	Guarantee Obligations Current Carrying Value GuaranteeObligationsCurrentCarryingValue	550000	USD
CY2018Q4	us-gaap	Guarantee Obligations Current Carrying Value GuaranteeObligationsCurrentCarryingValue	75000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20390000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	16993000	USD
	us-gaap	Net Income Loss NetIncomeLoss	59661000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52509000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26986000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26622000
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.64
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.22
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26701000
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.97
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26924000
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.96
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.21
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26986000
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26701000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26924000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26622000
CY2019Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	41000
CY2018Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	114000
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	52000
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	114000
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	27027000
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26815000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26976000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26736000
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
CY2019Q2	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions	909000	USD
CY2019Q2	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1003000	USD
CY2019Q2	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	269000	USD

Files In Submission

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0001171843-19-007133-index-headers.html	Edgar Link	pending
0001171843-19-007133-index.html	Edgar Link	pending
0001171843-19-007133.txt	Edgar Link	pending
0001171843-19-007133-xbrl.zip	Edgar Link	pending
ex_161876.htm	Edgar Link	pending
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FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending
wabc-20190930.xsd	Edgar Link	pending
wabc-20190930_cal.xml	Edgar Link	unprocessable
wabc-20190930_def.xml	Edgar Link	unprocessable
wabc-20190930_lab.xml	Edgar Link	unprocessable
wabc-20190930_pre.xml	Edgar Link	unprocessable
wabc20190930_10q.htm	Edgar Link	pending
wabc20190930_10q_htm.xml	Edgar Link	completed

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$WABC
Westamerica Bancorp Stock $wabc

2019 Q4 Form 10-Q Financial Statement

#000117184319007133 Filed on November 04, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WABC Westamerica Bancorp Stock $wabc

2019 Q4 Form 10-Q Financial Statement

#000117184319007133 Filed on November 04, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WABC
Westamerica Bancorp Stock $wabc