SUBORDINATED DEBENTURES AND SUBORDINATED NOTES - Summary of Subordinated Notes Outstanding (Details) - USD ($)		12 Months Ended
	Dec. 08, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	May 19, 2017
Subordinated Borrowing [Line Items]
Subordinated debentures and subordinated notes		$ 47,737,000	$ 47,492,000
Proceeds from issuance of subordinated notes, net	$ 33,900,000	0	33,876,000	$ 0
Notes
Subordinated Borrowing [Line Items]
Subordinated debentures and subordinated notes	$ 35,000,000	35,000,000	35,000,000		$ 34,000,000
Less: unamortized debt issuance costs		(1,291,000)	(1,115,000)
Proceeds from issuance of subordinated notes, net		$ 33,709,000	$ 33,885,000
Interest rate	8.50%	8.50%			8.50%