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Income Taxes - Effective Income Tax Reconciliation (Details) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Percent |  |  |
Federal statutory income tax rate | 21.00% | 21.00% | 21.00%
California franchise tax, net of federal tax benefit | 8.40% | 8.10% | 8.20%
Tax exempt interest on municipal securities and loans | (2.50%) | (2.40%) | (1.80%)
Tax exempt earnings on bank owned life insurance | (1.00%) | (0.50%) | (0.60%)
Non-deductible acquisition related expenses | 0.60% | 0.00% | 0.00%
Non-deductible executive compensation | 0.40% | 0.00% | 0.00%
Low income housing and qualified zone academy bond tax credits | (0.40%) | (0.50%) | (0.40%)
Stock-based compensation and excess tax benefits | (0.10%) | (0.20%) | (0.10%)
Other | (0.40%) | 0.00% | (0.90%)
Effective Tax Rate | 26.00% | 25.50% | 25.40%

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