EMPLOYEE BENEFITS - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Retirement Benefits [Abstract]
Employee stock ownership plan, maximum employer contribution as a percentage of participant's qualified compensation	5.00%
Employee stock ownership plan, total contributions accrued or paid	$ 445	$ 491
Employee stock ownership plan, fair value of shares subject to repurchase obligation			$ 31,661
Employee stock ownership plan, shares held under plan (in shares)	1,319,225		1,319,225
Employee stock ownership plan, unallocated shares (in shares)	50,000		50,000
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of life insurance	$ 18,035		$ 17,804
Bonus expense	1,103	931
Unfunded Plan | Nonqualified Plan | Executive Incentive Retirement Plan | Postretirement Life Insurance
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of life insurance	18,035		17,804
Plan cost	317	$ 275
Plan obligation	$ 2,305		$ 2,002