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Income Taxes - Statutory to Effective Tax Rate Reconciliation (Details) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax Disclosure [Abstract] |  |  |
Statutory tax rate | 21.00% | 21.00% | 35.00%
Low income housing tax credits | (3.30%) | (2.50%) | (2.90%)
Tax-exempt interest | (2.10%) | (2.10%) | (4.00%)
Bank owned life insurance | (0.40%) | (0.40%) | (0.80%)
Gain on sale of a majority interest of insurance business | 0.00% | 0.70% | 0.00%
Merger related expenses | 0.30% | 0.00% | 0.00%
Other | 0.80% | 0.30% | 0.30%
Impact of the Tax Act | 0.00% | (2.50%) | 11.30%
Effective Tax Rate | 16.30% | 14.50% | 38.90%

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