INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income tax expense	$ 5,478	$ 5,042	$ 14,543	$ 12,742
Income before income tax expense	$ 16,817	$ 15,945	$ 46,192	$ 41,907
Effective tax rate	32.60%	31.60%	31.50%	30.40%
Windfall tax benefits, net(1)	(0.20%)	(0.40%)	(0.40%)	(1.00%)
BOLI death benefit income (non-taxable)	(0.00%)	(0.00%)	(0.00%)	(0.30%)

Effective Income Tax Rate Reconciliation, Windfall Tax Benefit, Percent

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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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-Name Accounting Standards Codification
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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 life insurance expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SAB TOPIC 6.I)
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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

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-Topic 235
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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