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Income Taxes - Effective Income Tax Reconciliation (Details) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
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 | 8.10% | 8.20% | 8.00%
Tax exempt interest on municipal securities and loans | (2.40%) | (1.80%) | (2.40%)
Tax exempt earnings on bank owned life insurance | (0.50%) | (0.60%) | (0.40%)
Low income housing and qualified zone academy bond tax credits | (0.50%) | (0.40%) | (0.50%)
Stock-based compensation and excess tax benefits | (0.20%) | (0.10%) | (0.60%)
Other | 0.00% | (0.90%) | (0.20%)
Effective Tax Rate | 25.50% | 25.40% | 24.90%

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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