EMPLOYEE BENEFIT PLANS - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Defined benefits plan minimum requisite service period	90 days
Employer discretionary contribution amount paid	$ 0
Employers discretionary contribution annual vesting percentage	20.00%
Employers discretionary contribution, vesting period	5 years
Employer matching contributions to the plan	$ 500,000	$ 400,000	$ 400,000
Deferred compensation arrangement with individual distributions paid	$ 2,000
Defined benefit plan with maximum contractual term	2020
Minimum
Defined Benefit Plan Disclosure [Line Items]
Employee benefit plan requisite minimum age	21 years
Maximum
Defined Benefit Plan Disclosure [Line Items]
Employer matching contributions percentage on employees matching annual salary	4.00%
Citizens Bancshares, Inc.
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation arrangement with individual distributions paid	$ 5,500
Defined benefit plan with maximum contractual term	2030
Accrued Taxes And Other Liabilities
Defined Benefit Plan Disclosure [Line Items]
Liability recorded on balance sheet related to plans	$ (700,000)	$ (100,000)