RESTRICTION ON CASH AND DUE FROM BANKS - Reserve Funds (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
RESTRICTION ON CASH AND DUE FROM BANKS
Required reserve funds in cash or on deposit with the Federal Reserve Bank	$ 11,557	$ 33,844
Compensating balance requirements for funds in cash or on deposit with the Federal Reserve Bank	$ 0

The amount of a specific compensating balance arrangement that is maintained under an agreement for a bank loan or future credit availability.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_CompensatingBalanceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant