ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY - Balance In The Allowance For Loan Losses And The Recorded Investment In Loans By Portfolio Management (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 7,662	$ 10,384
Collectively evaluated for impairment	45,947	40,268
Total ending allowance balance	53,609	50,652	$ 49,562	$ 48,453
Loans:
Loans individually evaluated for impairment	22,978	27,829
Loans collectively evaluated for impairment	4,062,760	4,037,999
Total ending loans balance	4,085,738	4,065,828
Commercial and Industrial Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	6,676	9,324
Collectively evaluated for impairment	18,063	16,465
Total ending allowance balance	24,739	25,789	24,030	22,518
Loans:
Loans individually evaluated for impairment	15,726	19,580
Loans collectively evaluated for impairment	1,412,920	1,407,246
Total ending loans balance	1,428,646	1,426,826
Commercial Real Estate and Multi-family Residential Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	502	538
Collectively evaluated for impairment	18,156	15,258
Total ending allowance balance	18,658	15,796	15,447	15,393
Loans:
Loans individually evaluated for impairment	4,127	4,998
Loans collectively evaluated for impairment	1,754,085	1,665,842
Total ending loans balance	1,758,212	1,670,840
Agri-business and Agricultural Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	57	90
Collectively evaluated for impairment	3,647	3,779
Total ending allowance balance	3,704	3,869	4,146	4,305
Loans:
Loans individually evaluated for impairment	430	445
Loans collectively evaluated for impairment	329,067	379,186
Total ending loans balance	329,497	379,631
Other Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	521	447
Total ending allowance balance	521	447	373	368
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	104,163	112,166
Total ending loans balance	104,163	112,166
Consumer 1-4 Family Mortgage Loans [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	427	426
Collectively evaluated for impairment	2,048	1,660
Total ending allowance balance	2,475	2,086	2,266	2,292
Loans:
Loans individually evaluated for impairment	2,695	2,789
Loans collectively evaluated for impairment	365,666	375,210
Total ending loans balance	368,361	377,999
Other Consumer
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	6
Collectively evaluated for impairment	447	339
Total ending allowance balance	447	345	291	283
Loans:
Loans individually evaluated for impairment	0	17
Loans collectively evaluated for impairment	96,859	98,349
Total ending loans balance	96,859	98,366
Unallocated
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	3,065	2,320
Total ending allowance balance	3,065	2,320	$ 3,009	$ 3,294
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	0	0
Total ending loans balance	$ 0	$ 0

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

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

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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