SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE - Summary of Securities Sold Under Repurchase Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	$ 20,635	$ 20,384
Weighted Average
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	$ 14,043	$ 15,692	$ 28,694
Average interest rate during the year	0.61%	0.15%	0.20%
Weighted average interest rate at year-end	0.81%	0.14%	0.18%
Maximum
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	$ 23,626	$ 23,270	$ 49,836