INVESTMENT SECURITIES AVAILABLE FOR SALE - Additional Information (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities	$ 374,600,000				$ 337,100,000				$ 374,600,000	$ 337,100,000
Other than temporary impairment charges									0	0	$ 0
Securities gains/(losses), net	$ (45,000)	$ 34,000	$ 69,000	$ 59,000	$ 46,000	$ (325,000)	$ (36,000)	$ (78,000)	117,000	(393,000)
CRA Investment Fund [Member]
Schedule Of Available For Sale Securities [Line Items]
Securities gains/(losses), net									$ 117,000	$ (105,000)