LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Allowance for loan losses
Total loans	$ 2,708,691	$ 2,641,092
Total commercial real estate
Allowance for loan losses
Total loans	1,045,635	930,661
Commercial and industrial
Allowance for loan losses
Total loans	522,510	423,291
Total residential real estate
Allowance for loan losses
Total loans	1,021,206	1,151,857
Total consumer
Allowance for loan losses
Total loans	119,340	135,283
Business Activities Loans
Allowance for loan losses
Individually evaluated for impairment	6,105	7,950
Collectively evaluated	2,050,741	1,827,280
Total loans	2,056,846	1,835,230
Business Activities Loans \| Total commercial real estate
Allowance for loan losses
Individually evaluated for impairment	2,586	3,964
Collectively evaluated	849,812	693,474
Total loans	852,398	697,438
Business Activities Loans \| Commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	1,274	1,353
Collectively evaluated	439,847	325,217
Total loans	441,121	326,570
Business Activities Loans \| Total residential real estate
Allowance for loan losses
Individually evaluated for impairment	2,233	2,620
Collectively evaluated	693,533	738,067
Total loans	695,766	740,687
Business Activities Loans \| Total consumer
Allowance for loan losses
Individually evaluated for impairment	12	13
Collectively evaluated	67,549	70,522
Total loans	67,561	70,535
Acquired Loans
Allowance for loan losses
Individually evaluated for impairment	3,512	1,675
Purchased credit impaired	14,198	18,553
Collectively evaluated	634,135	785,634
Total loans	651,845	805,862
Acquired Loans \| Total commercial real estate
Allowance for loan losses
Individually evaluated for impairment	2,358	258
Purchased credit impaired	7,448	8,673
Collectively evaluated	183,431	224,292
Total loans	193,237	233,223
Acquired Loans \| Commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	322	385
Purchased credit impaired	1,338	2,932
Collectively evaluated	79,729	93,404
Total loans	81,389	96,721
Acquired Loans \| Total residential real estate
Allowance for loan losses
Individually evaluated for impairment	832	1,032
Purchased credit impaired	4,657	5,591
Collectively evaluated	319,951	404,547
Total loans	325,440	411,170
Acquired Loans \| Total consumer
Allowance for loan losses
Purchased credit impaired	755	1,357
Collectively evaluated	51,024	63,391
Total loans	$ 51,779	$ 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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