INCOME TAXES, Effective Tax Rate Reconciliation (Details)	12 Months Ended
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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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section S99
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-Publisher FASB
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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