LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Allowance for loan losses
Total loans	$ 2,634,983	$ 2,641,092
Total commercial real estate
Allowance for loan losses
Total loans	948,178	930,661
Commercial and industrial
Allowance for loan losses
Total loans	426,357	423,291
Residential real estate
Allowance for loan losses
Total loans	1,132,328	1,151,857
Consumer
Allowance for loan losses
Total loans	128,120	135,283
Business Activities Loans
Allowance for loan losses
Individually evaluated for impairment	7,970	7,950
Collectively evaluated	1,900,588	1,827,280
Total loans	1,908,558	1,835,230
Business Activities Loans \| Total commercial real estate
Allowance for loan losses
Individually evaluated for impairment	2,638	3,964
Collectively evaluated	727,097	693,474
Total loans	729,735	697,438
Business Activities Loans \| Commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	1,733	1,353
Collectively evaluated	360,640	325,217
Total loans	362,373	326,570
Business Activities Loans \| Residential real estate
Allowance for loan losses
Individually evaluated for impairment	3,586	2,620
Collectively evaluated	739,124	738,067
Total loans	742,710	740,687
Business Activities Loans \| Consumer
Allowance for loan losses
Individually evaluated for impairment	13	13
Collectively evaluated	73,727	70,522
Total loans	73,740	70,535
Acquired Loans
Allowance for loan losses
Individually evaluated for impairment	366	1,675
Purchased credit impaired	15,175	18,553
Collectively evaluated	710,884	785,634
Total loans	726,425	805,862
Acquired Loans \| Total commercial real estate
Allowance for loan losses
Individually evaluated for impairment	70	258
Purchased credit impaired	7,520	8,673
Collectively evaluated	210,853	224,292
Total loans	218,443	233,223
Acquired Loans \| Commercial and industrial
Allowance for loan losses
Individually evaluated for impairment		385
Purchased credit impaired	1,952	2,932
Collectively evaluated	62,032	93,404
Total loans	63,984	96,721
Acquired Loans \| Residential real estate
Allowance for loan losses
Individually evaluated for impairment	296	1,032
Purchased credit impaired	4,856	5,591
Collectively evaluated	384,466	404,547
Total loans	389,618	411,170
Acquired Loans \| Consumer
Allowance for loan losses
Purchased credit impaired	847	1,357
Collectively evaluated	53,533	63,391
Total loans	$ 54,380	$ 64,748

The carrying amount as of the balance sheet date of loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer, for which it was deemed probable at acquisition that the investor would be unable to collect all contractually required payments, and to which the income recognition total model was not applied.

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

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Amount before allowance and after 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.

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