FAIR VALUE - IMPAIRED LOANS (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Impaired loans
Carrying amount of loans measured at fair value	$ 22,669	$ 21,880
Valuation allowance	(3,594)	(3,764)
Nonrecurring basis
Impaired loans
Total fair value	7,282	7,935
Fair Value, Inputs, Level 3 | Nonrecurring basis
Impaired loans
Carrying amount of loans measured at fair value	6,761	7,380
Estimated selling costs considered in carrying amount	881	913
Valuation allowance	(360)	(358)
Total fair value	7,282	7,935
Provision for impairment on loan, lease and other losses
Provisions on collateral-dependent, impaired loans	$ 14	$ 429