LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Loans receivable: balance at end of period
Total	$ 2,376,647	$ 1,129,064
Commercial real estate
Loans receivable: balance at end of period
Total	738,584	418,119
Commercial and industrial
Loans receivable: balance at end of period
Total	350,002	151,240
Residential real estate
Loans receivable: balance at end of period
Total	1,160,832	506,612
Consumer
Loans receivable: balance at end of period
Total	127,229	53,093
Business Activities Loans
Loans receivable: balance at end of period
Individually evaluated for impairment	6,314	6,709
Collectively evaluated	1,257,624	1,122,355
Total	1,263,938	1,129,064
Business Activities Loans \| Commercial real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	3,916	4,481
Collectively evaluated	426,838	413,638
Total	430,754	418,119
Business Activities Loans \| Commercial and industrial
Loans receivable: balance at end of period
Individually evaluated for impairment	479	486
Collectively evaluated	227,672	150,754
Total	228,151	151,240
Business Activities Loans \| Residential real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	1,858	1,709
Collectively evaluated	547,720	504,903
Total	549,578	506,612
Business Activities Loans \| Consumer
Loans receivable: balance at end of period
Individually evaluated for impairment	61	33
Collectively evaluated	55,394	53,060
Total	55,455	53,093
Acquired Loans
Loans receivable: balance at end of period
Individually evaluated for impairment	0
Purchased credit-impaired loans	15,633
Collectively evaluated	1,097,076
Total	1,112,709	0
Acquired Loans \| Commercial real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	0
Purchased credit-impaired loans	10,716
Collectively evaluated	297,114
Total	307,830	0
Acquired Loans \| Commercial and industrial
Loans receivable: balance at end of period
Individually evaluated for impairment	0
Purchased credit-impaired loans	1,217
Collectively evaluated	120,634
Total	121,851	0
Acquired Loans \| Residential real estate
Loans receivable: balance at end of period
Individually evaluated for impairment	0
Purchased credit-impaired loans	3,640
Collectively evaluated	607,614
Total	611,254	0
Acquired Loans \| Consumer
Loans receivable: balance at end of period
Individually evaluated for impairment	0
Purchased credit-impaired loans	60
Collectively evaluated	71,714
Total	$ 71,774	$ 0

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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