LOANS - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	$ 60,869	$ 49,911
Charge-offs	(8,965)
Recoveries	6,118
Provision	(8,839)	14,212	$ 8,430
Balance, end of period	49,869	60,869	49,911
PCD Loans [Member]
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period		0
Balance, end of period			0
Commercial Portfolio Segment \| Business Lending
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period		19,426
Balance, end of period			19,426
Commercial Portfolio Segment \| Consumer Mortgage
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period		10,269
Balance, end of period			10,269
Consumer Portfolio Segment \| Business Lending
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	28,190
Charge-offs	(1,618)
Recoveries	689
Balance, end of period	21,021	28,190
Consumer Portfolio Segment \| Consumer Mortgage
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	10,672
Charge-offs	(426)
Recoveries	91
Balance, end of period	10,017	10,672
Consumer Portfolio Segment \| Consumer Indirect
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	13,696	13,712
Charge-offs	(5,160)
Recoveries	4,346
Balance, end of period	11,737	13,696	13,712
Consumer Portfolio Segment \| Consumer Direct
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	3,207	3,255
Charge-offs	(1,232)
Recoveries	793
Balance, end of period	2,306	3,207	3,255
Consumer Portfolio Segment \| Home Equity
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	2,222	2,129
Charge-offs	(225)
Recoveries	92
Balance, end of period	1,814	2,222	2,129
Unallocated Financing Receivables [Member]
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	1,000	957
Charge-offs	0
Recoveries	0
Balance, end of period	1,000	1,000	957
Topic ASC 326 [Member]
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	60,869	51,268
Charge-offs		(10,664)
Recoveries		5,689
Balance, end of period		60,869	51,268
Topic ASC 326 [Member] \| PCD Loans [Member]
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	1,882	3,072
Charge-offs		(91)
Recoveries		440
Balance, end of period		1,882	3,072
Topic ASC 326 [Member] \| Commercial Portfolio Segment \| Business Lending
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	28,190	19,714
Charge-offs		(1,497)
Recoveries		356
Provision		7,274
Balance, end of period		28,190	19,714
Topic ASC 326 [Member] \| Commercial Portfolio Segment \| Consumer Mortgage
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	10,672	9,218
Charge-offs		(862)
Recoveries		130
Balance, end of period		10,672	9,218
Topic ASC 326 [Member] \| Consumer Portfolio Segment \| Consumer Indirect
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	13,696	12,715
Charge-offs		(6,382)
Recoveries		3,992
Balance, end of period		13,696	12,715
Topic ASC 326 [Member] \| Consumer Portfolio Segment \| Consumer Direct
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	3,207	2,612
Charge-offs		(1,633)
Recoveries		743
Balance, end of period		3,207	2,612
Topic ASC 326 [Member] \| Consumer Portfolio Segment \| Home Equity
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	2,222	2,937
Charge-offs		(199)
Recoveries		28
Balance, end of period		2,222	2,937
Topic ASC 326 [Member] \| Unallocated Financing Receivables [Member]
Allowance for credit losses - loans [Roll Forward]
Balance, beginning of period	$ 1,000	1,000
Charge-offs		0
Recoveries		0
Balance, end of period		$ 1,000	$ 1,000

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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.

+ References

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Amount of expense related to estimated loss from loan and lease transactions.

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