LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Loans receivable: balance at end of period
Total	$ 2,483,590	$ 2,485,613
Commercial real estate
Loans receivable: balance at end of period
Total	840,018	826,746
Commercial and industrial
Loans receivable: balance at end of period
Total	385,814	379,423
Residential real estate
Loans receivable: balance at end of period
Total	1,140,519	1,155,682
Consumer
Loans receivable: balance at end of period
Total	117,239	123,762
Business Activities Loans
Loans receivable: balance at end of period
Individually evaluated for impairment	15,551	9,647
Collectively evaluated	1,571,621	1,442,983
Total	1,587,172	1,452,630
Business Activities Loans \| Commercial real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	9,016	7,604
Collectively evaluated	576,150	526,407
Total	585,166	534,011
Business Activities Loans \| Commercial and industrial
Loans receivable: balance at end of period
Individually evaluated for impairment	1,435	626
Collectively evaluated	291,586	267,378
Total	293,021	268,004
Business Activities Loans \| Residential real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	4,940	1,404
Collectively evaluated	638,098	590,007
Total	643,038	591,411
Business Activities Loans \| Consumer
Loans receivable: balance at end of period
Individually evaluated for impairment	160	13
Collectively evaluated	65,787	59,191
Total	65,947	59,204
Acquired Loans
Loans receivable: balance at end of period
Individually evaluated for impairment	989	1,146
Purchased credit impaired	10,677	12,587
Collectively evaluated	884,752	1,019,250
Total	896,418	1,032,983
Acquired Loans \| Commercial real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	98	241
Purchased credit impaired	6,994	8,655
Collectively evaluated	247,760	283,839
Total	254,852	292,735
Acquired Loans \| Commercial and industrial
Loans receivable: balance at end of period
Individually evaluated for impairment	426	571
Purchased credit impaired	563	632
Collectively evaluated	91,804	110,216
Total	92,793	111,419
Acquired Loans \| Residential real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	465	271
Purchased credit impaired	3,094	3,259
Collectively evaluated	493,922	560,741
Total	497,481	564,271
Acquired Loans \| Consumer
Loans receivable: balance at end of period
Individually evaluated for impairment	0	63
Purchased credit impaired	26	41
Collectively evaluated	51,266	64,454
Total	$ 51,292	$ 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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-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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