LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Allowance for loan losses
Loans and Leases Receivable, Net Amount	$ 2,543,803	$ 2,619,240
Total loans	2,562,885	2,634,593
Total commercial real estate
Allowance for loan losses
Total loans	1,084,381	930,661
Total commercial and industrial
Allowance for loan losses
Total loans	441,069	423,291
Total residential real estate
Allowance for loan losses
Total loans	923,891	1,145,358
Total consumer
Allowance for loan losses
Total loans	113,544	135,283
Business Activities Loans
Allowance for loan losses
Individually evaluated for impairment	5,446	7,950
Collectively evaluated	1,959,308	1,820,781
Total loans	1,964,754	1,828,731
Business Activities Loans \| Total commercial real estate
Allowance for loan losses
Individually evaluated for impairment	2,222	3,964
Collectively evaluated	892,895	693,474
Total loans	895,117	697,438
Business Activities Loans \| Total commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	997	1,353
Collectively evaluated	370,234	325,217
Total loans	371,231	326,570
Business Activities Loans \| Total residential real estate
Allowance for loan losses
Individually evaluated for impairment	2,215	2,620
Collectively evaluated	631,175	731,568
Total loans	633,390	734,188
Business Activities Loans \| Total consumer
Allowance for loan losses
Individually evaluated for impairment	12	13
Collectively evaluated	65,004	70,522
Total loans	65,016	70,535
Acquired Loans
Allowance for loan losses
Individually evaluated for impairment	3,300	1,675
Purchased credit impaired	12,686	18,553
Collectively evaluated	582,145	785,634
Total loans	598,131	805,862
Acquired Loans \| Total commercial real estate
Allowance for loan losses
Individually evaluated for impairment	2,338	258
Purchased credit impaired	6,433	8,673
Collectively evaluated	180,493	224,292
Total loans	189,264	233,223
Acquired Loans \| Total commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	294	385
Purchased credit impaired	1,023	2,932
Collectively evaluated	68,521	93,404
Total loans	69,838	96,721
Acquired Loans \| Total residential real estate
Allowance for loan losses
Individually evaluated for impairment	668	1,032
Purchased credit impaired	4,532	5,591
Collectively evaluated	285,301	404,547
Total loans	290,501	411,170
Acquired Loans \| Total consumer
Allowance for loan losses
Purchased credit impaired	698	1,357
Collectively evaluated	47,830	63,391
Total loans	48,528	64,748
Construction and land development \| Total commercial real estate
Allowance for loan losses
Total loans	131,123	34,290
Construction and land development \| Business Activities Loans \| Total commercial real estate
Allowance for loan losses
Total loans	129,255	31,387
Construction and land development \| Acquired Loans \| Total commercial real estate
Allowance for loan losses
Purchased credit impaired	74	384
Total loans	1,868	2,903
Tax exempt \| Total commercial and industrial
Allowance for loan losses
Total loans	63,431	104,303
Tax exempt \| Business Activities Loans \| Total commercial and industrial
Allowance for loan losses
Total loans	39,429	66,860
Tax exempt \| Acquired Loans \| Total commercial and industrial
Allowance for loan losses
Purchased credit impaired		36
Total loans	24,002	37,443
Residential mortgages \| Total residential real estate
Allowance for loan losses
Total loans	923,891	1,145,358
Residential mortgages \| Business Activities Loans \| Total residential real estate
Allowance for loan losses
Total loans	633,390	734,188
Residential mortgages \| Acquired Loans \| Total residential real estate
Allowance for loan losses
Purchased credit impaired	4,532	5,591
Total loans	290,501	411,170
Home equity \| Total consumer
Allowance for loan losses
Total loans	102,464	122,401
Home equity \| Business Activities Loans \| Total consumer
Allowance for loan losses
Total loans	55,092	59,368
Home equity \| Acquired Loans \| Total consumer
Allowance for loan losses
Purchased credit impaired	659	1,291
Total loans	47,372	63,033
Other consumer \| Total consumer
Allowance for loan losses
Total loans	11,080	12,882
Other consumer \| Business Activities Loans \| Total consumer
Allowance for loan losses
Total loans	9,924	11,167
Other consumer \| Acquired Loans \| Total consumer
Allowance for loan losses
Purchased credit impaired	39	66
Total loans	$ 1,156	$ 1,715

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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