NONINTEREST INCOME - Deposit service charges (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Service fees
Revenue from External Customer [Line Items]
Deposit service charges	$ 3,116	$ 3,188	$ 9,246	$ 9,083
Return and overdraft fees
Revenue from External Customer [Line Items]
Deposit service charges	1,532	2,797	4,998	7,341
Other deposit service fees
Revenue from External Customer [Line Items]
Deposit service charges	124	154	350	564
Deposit service charges
Revenue from External Customer [Line Items]
Deposit service charges	$ 4,772	$ 6,139	$ 14,594	$ 16,988

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details