NONINTEREST INCOME - Deposit service charges (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Service fees
Revenue from External Customer [Line Items]
Deposit service charges	$ 3,553	$ 2,919	$ 6,975	$ 6,130
Return and overdraft fees
Revenue from External Customer [Line Items]
Deposit service charges	1,504	1,134	3,082	3,466
Other deposit service fees
Revenue from External Customer [Line Items]
Deposit service charges	262	122	722	226
Deposit service charges
Revenue from External Customer [Line Items]
Deposit service charges	$ 5,319	$ 4,175	$ 10,779	$ 9,822