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	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 10,384	$ 10,029
Collectively evaluated for impairment	40,268	38,424
Total ending allowance balance	50,652	48,453	$ 47,121	$ 43,718
Loans:
Loans individually evaluated for impairment	27,829	26,717
Loans collectively evaluated for impairment	4,037,999	3,888,028
Total ending loans balance	4,065,828	3,914,745
Commercial and Industrial Loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	9,324	8,552
Collectively evaluated for impairment	16,465	13,966
Total ending allowance balance	25,789	22,518	21,097	20,272
Loans:
Loans individually evaluated for impairment	19,580	19,734
Loans collectively evaluated for impairment	1,407,246	1,385,604
Total ending loans balance	1,426,826	1,405,338
Commercial Real Estate and Multi-family Residential Loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	538	921
Collectively evaluated for impairment	15,258	14,472
Total ending allowance balance	15,796	15,393	14,714	13,452
Loans:
Loans individually evaluated for impairment	4,998	4,266
Loans collectively evaluated for impairment	1,665,842	1,562,899
Total ending loans balance	1,670,840	1,567,165
Agri-business and Agricultural Loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	90	73
Collectively evaluated for impairment	3,779	4,232
Total ending allowance balance	3,869	4,305	4,920	3,532
Loans:
Loans individually evaluated for impairment	445	433
Loans collectively evaluated for impairment	379,186	370,174
Total ending loans balance	379,631	370,607
Other Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	447	368
Total ending allowance balance	447	368	577	461
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	112,166	95,520
Total ending loans balance	112,166	95,520
Consumer 1-4 Family Mortgage Loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	426	457
Collectively evaluated for impairment	1,660	1,835
Total ending allowance balance	2,086	2,292	2,768	2,827
Loans:
Loans individually evaluated for impairment	2,789	2,240
Loans collectively evaluated for impairment	375,210	388,053
Total ending loans balance	377,999	390,293
Other Consumer
Ending allowance balance attributable to loans:
Individually evaluated for impairment	6	26
Collectively evaluated for impairment	339	257
Total ending allowance balance	345	283	379	387
Loans:
Loans individually evaluated for impairment	17	44
Loans collectively evaluated for impairment	98,349	85,778
Total ending loans balance	98,366	85,822
Unallocated
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	2,320	3,294
Total ending allowance balance	2,320	3,294	$ 2,666	$ 2,787
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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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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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