NONINTEREST INCOME - Other income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Managed service fees
Revenue from External Customer [Line Items]
Noninterest fee income	$ 4,031	$ 2,943
Currency preparation
Revenue from External Customer [Line Items]
Noninterest fee income	840	739
ATM insurance
Revenue from External Customer [Line Items]
Noninterest fee income	647	627
Miscellaneous products and services
Revenue from External Customer [Line Items]
Noninterest fee income	1,435	3,398
Other income
Revenue from External Customer [Line Items]
Noninterest fee income	$ 6,953	$ 7,707

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration