NONINTEREST INCOME - Deposit service charges (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Service fees
Revenue from External Customer [Line Items]
Deposit service charges	$ 3,422	$ 3,211
Return and overdraft fees
Revenue from External Customer [Line Items]
Deposit service charges	1,578	2,332
Other deposit service fees
Revenue from External Customer [Line Items]
Deposit service charges	460	104
Deposit service charges
Revenue from External Customer [Line Items]
Deposit service charges	$ 5,460	$ 5,647

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