LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Loans receivable: balance at end of period
Total	$ 2,464,419	$ 2,485,613
Commercial real estate
Loans receivable: balance at end of period
Total	824,721	826,746
Commercial and industrial
Loans receivable: balance at end of period
Total	387,205	379,423
Residential real estate
Loans receivable: balance at end of period
Total	1,132,977	1,155,682
Consumer
Loans receivable: balance at end of period
Total	119,516	123,762
Business Activities Loans
Loans receivable: balance at end of period
Individually evaluated for impairment	13,893	9,647
Collectively evaluated	1,457,123	1,442,983
Total	1,471,016	1,452,630
Business Activities Loans \| Commercial real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	7,641	7,604
Collectively evaluated	535,525	526,407
Total	543,166	534,011
Business Activities Loans \| Commercial and industrial
Loans receivable: balance at end of period
Individually evaluated for impairment	1,504	626
Collectively evaluated	278,201	267,378
Total	279,705	268,004
Business Activities Loans \| Residential real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	4,386	1,404
Collectively evaluated	584,079	590,007
Total	588,465	591,411
Business Activities Loans \| Consumer
Loans receivable: balance at end of period
Individually evaluated for impairment	362	13
Collectively evaluated	59,318	59,191
Total	59,680	59,204
Acquired Loans
Loans receivable: balance at end of period
Individually evaluated for impairment	1,234	1,146
Purchased Credit Impaired	12,265	12,587
Collectively evaluated	979,904	1,019,250
Total	993,403	1,032,983
Acquired Loans \| Commercial real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	133	241
Purchased Credit Impaired	8,610	8,655
Collectively evaluated	272,812	283,839
Total	281,555	292,735
Acquired Loans \| Commercial and industrial
Loans receivable: balance at end of period
Individually evaluated for impairment	598	571
Purchased Credit Impaired	459	632
Collectively evaluated	106,443	110,216
Total	107,500	111,419
Acquired Loans \| Residential real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	503	271
Purchased Credit Impaired	3,168	3,259
Collectively evaluated	540,841	560,741
Total	544,512	564,271
Acquired Loans \| Consumer
Loans receivable: balance at end of period
Individually evaluated for impairment	0	63
Purchased Credit Impaired	28	41
Collectively evaluated	59,808	64,454
Total	$ 59,836	$ 64,558

Financing Receivable, Purchased Credit-Impaired Loans

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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

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- References

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