NONINTEREST INCOME - Deposit service charges (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Service fees
Revenue from External Customer [Line Items]
Deposit service charges	$ 2,919	$ 3,179	$ 6,130	$ 5,895
Return and overdraft fees
Revenue from External Customer [Line Items]
Deposit service charges	1,134	2,696	3,466	4,544
Other deposit service fees
Revenue from External Customer [Line Items]
Deposit service charges	122	228	226	410
Deposit service charges
Revenue from External Customer [Line Items]
Deposit service charges	$ 4,175	$ 6,103	$ 9,822	$ 10,849