REVENUE RECOGNITION - Summary of Noninterest Income (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Noninterest income (in-scope of Topic 606)	$ 1,081		$ 976	$ 2,705	$ 3,264
Noninterest income (out-of-scope of Topic 606)	2,873		2,205	8,838	3,922
Total noninterest income	3,954	$ 5,528	3,181	11,543	7,186
Deposit service fees
Disaggregation of Revenue [Line Items]
Noninterest income (in-scope of Topic 606)	648		599	1,607	1,841
Debit card fees
Disaggregation of Revenue [Line Items]
Noninterest income (in-scope of Topic 606)	384		138	941	429
Investment commissions
Disaggregation of Revenue [Line Items]
Noninterest income (in-scope of Topic 606)	0		146	0	685
Other
Disaggregation of Revenue [Line Items]
Noninterest income (in-scope of Topic 606)	$ 49		$ 93	$ 157	$ 309