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INCOME TAXES, Effective Tax Rate Reconciliation (Details) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Effective tax rate reconciliation [Abstract] |  |  |
Federal statutory income tax rate | 35.00% | 35.00% | 35.00%
Increase (reduction) in taxes resulting from [Abstract] |  |  |
Tax-exempt interest | (4.00%) | (5.00%) | (5.40%)
State income taxes, net of federal benefit | 2.70% | 1.80% | 0.70%
Other | (0.90%) | (0.80%) | (0.70%)
Effective income tax rate | 32.80% | 31.00% | 29.60%

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