LOANS AND LEASES - Nonaccrual Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	$ 36,636		$ 36,636		$ 25,919
Financing Receivable, Nonaccrual, No Allowance	29,330		29,330		54,833
Nonaccrual loans	65,966		65,966		80,752
Interest income effect
Gross amount of interest that would have been recorded under original terms	3,506	$ 1,552	8,157	$ 4,185
Interest included in income
Nonaccrual loans	1,709	689	3,526	1,226
Troubled debt restructurings	338	64	645	367
Total interest included in income	2,047	753	4,171	1,593
Net impact on interest income	1,459	$ 799	3,986	$ 2,592
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	12,328		12,328		18,711
Financing Receivable, Nonaccrual, No Allowance	2,832		2,832		10,519
Nonaccrual loans	15,160		15,160		29,230
Lease financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0		0		0
Financing Receivable, Nonaccrual, No Allowance	0		0		0
Nonaccrual loans	0		0		0
Construction real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0		0		0
Financing Receivable, Nonaccrual, No Allowance	0		0		0
Nonaccrual loans	0		0		0
Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	24,308		24,308		6,957
Financing Receivable, Nonaccrual, No Allowance	14,256		14,256		27,725
Nonaccrual loans	38,564		38,564		34,682
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0		0		251
Financing Receivable, Nonaccrual, No Allowance	9,416		9,416		11,350
Nonaccrual loans	9,416		9,416		11,601
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0		0		0
Financing Receivable, Nonaccrual, No Allowance	2,735		2,735		5,076
Nonaccrual loans	2,735		2,735		5,076
Installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0		0		0
Financing Receivable, Nonaccrual, No Allowance	91		91		163
Nonaccrual loans	$ 91		$ 91		$ 163

Financing Receivable, Impaired, Interest Income that would have been recorded

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Financing Receivable, Impaired, Interest Income Recorded on Nonaccrual Loans

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Financing Receivable, Impaired, Interest Income Recorded on Restructured Loans

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Financing Receivable, Nonaccrual, With Allowance

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Amount of financing receivable on nonaccrual status with no allowance for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
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Amount of financing receivable on nonaccrual status.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Number 229
-Section 1405
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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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