FAIR VALUE DISCLOSURES - Certain assets measured on a non recurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Impaired Loans
Total loans	$ 2,330,704	$ 2,286,766
Level 3 Inputs \| Non-recurring basis
Impaired Loans
Total loans	5,547	2,698
Level 3 Inputs \| Non-recurring basis \| Commercial and industrial
Impaired Loans
Total loans	1,324	340
Level 3 Inputs \| Non-recurring basis \| Commercial real estate
Impaired Loans
Total loans	2,468	603
Level 3 Inputs \| Non-recurring basis \| 1-4 family residential
Impaired Loans
Total loans	$ 1,755	$ 1,755

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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