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Income Taxes - Effective Income Tax Reconciliation (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Percent
Federal statutory income tax rate	21.00%	21.00%
California franchise tax, net of federal tax benefit	8.20%	8.00%
Tax exempt interest on municipal securities and loans	(1.80%)	(2.40%)
Tax exempt earnings on bank owned life insurance	(0.60%)	(0.40%)
Low income housing and qualified zone academy bond tax credits	(0.40%)	(0.50%)
Stock-based compensation and excess tax benefits	(0.10%)	(0.60%)
Other	(0.90%)	(0.20%)
Effective Tax Rate	25.40%	24.90%

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Effective Income Tax Rate Reconciliation, Deduction, Share-Based Compensation And Excess Tax Benefits

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Earnings on Bank Owned Life Insurance

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Interest on Municipal Securities and Loans

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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