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LOANS AND LEASES - Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	$ 67,879		$ 67,879		$ 48,165
Current balance					59,600
Contractual Principal Balance					84,482
Related Allowance					2,175
Average current balance		$ 85,524		$ 85,952
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		53		117
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		408		915
Interest income recognized	438	461	840	1,032
Commercial
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	33,906		33,906		24,346
Current balance					27,480
Contractual Principal Balance					41,222
Related Allowance					2,044
Average current balance		40,404		39,481
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		43		86
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		212		491
Interest income recognized		255		577
Lease financing
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,353		1,353		223
Current balance					223
Contractual Principal Balance					223
Related Allowance					0
Average current balance		298		206
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		0		0
Interest income recognized		0		0
Construction real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	0		0		0
Current balance					0
Contractual Principal Balance					0
Related Allowance					0
Average current balance		7		8
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		0		0
Interest income recognized		0		0
Commercial real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	14,002		14,002		7,295
Current balance					10,831
Contractual Principal Balance					18,572
Related Allowance					113
Average current balance		22,438		23,299
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		4		23
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		98		201
Interest income recognized		102		224
Residential real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	12,813		12,813		10,892
Current balance					15,162
Contractual Principal Balance					17,662
Related Allowance					18
Average current balance		16,457		16,837
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		6		8
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		69		155
Interest income recognized		75		163
Home equity
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	5,604		5,604		5,242
Current balance					5,700
Contractual Principal Balance					6,462
Related Allowance					0
Average current balance		5,735		5,940
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		28		66
Interest income recognized		28		66
Installment
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	201		201		167
Current balance					204
Contractual Principal Balance					341
Related Allowance					0
Average current balance		185		181
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		1		2
Interest income recognized		1		2
Loans with no related allowance recorded [member]
Financing Receivable, Impaired [Line Items]
Current balance					47,881
Contractual Principal Balance					62,000
Related Allowance					0
Average current balance		77,296		79,550
Loans with no related allowance recorded [member] \| Commercial
Financing Receivable, Impaired [Line Items]
Current balance					16,726
Contractual Principal Balance					19,709
Related Allowance					0
Average current balance		34,553		35,267
Loans with no related allowance recorded [member] \| Lease financing
Financing Receivable, Impaired [Line Items]
Current balance					223
Contractual Principal Balance					223
Related Allowance					0
Average current balance		298		206
Loans with no related allowance recorded [member] \| Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance					0
Contractual Principal Balance					0
Related Allowance					0
Average current balance		7		8
Loans with no related allowance recorded [member] \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance					10,160
Contractual Principal Balance					17,897
Related Allowance					0
Average current balance		20,731		21,658
Loans with no related allowance recorded [member] \| Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance					14,868
Contractual Principal Balance					17,368
Related Allowance					0
Average current balance		15,787		16,290
Loans with no related allowance recorded [member] \| Home equity
Financing Receivable, Impaired [Line Items]
Current balance					5,700
Contractual Principal Balance					6,462
Related Allowance					0
Average current balance		5,735		5,940
Loans with no related allowance recorded [member] \| Installment
Financing Receivable, Impaired [Line Items]
Current balance					204
Contractual Principal Balance					341
Related Allowance					0
Average current balance		185		181
Impaired Financing Receivables With Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Current balance	33,311		33,311
Impaired Financing Receivables With Related Allowance [Member] \| Commercial
Financing Receivable, Impaired [Line Items]
Current balance	23,586		23,586		10,754
Contractual Principal Balance					21,513
Related Allowance					2,044
Average current balance		5,851		4,214
Impaired Financing Receivables With Related Allowance [Member] \| Lease financing
Financing Receivable, Impaired [Line Items]
Current balance					0
Contractual Principal Balance					0
Related Allowance					0
Average current balance		0		0
Impaired Financing Receivables With Related Allowance [Member] \| Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance					0
Contractual Principal Balance					0
Related Allowance					0
Average current balance		0		0
Impaired Financing Receivables With Related Allowance [Member] \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance					671
Contractual Principal Balance					675
Related Allowance					113
Average current balance		1,707		1,641
Impaired Financing Receivables With Related Allowance [Member] \| Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance	$ 1,252		$ 1,252		294
Contractual Principal Balance					294
Related Allowance					18
Average current balance		670		547
Impaired Financing Receivables With Related Allowance [Member] \| Home equity
Financing Receivable, Impaired [Line Items]
Current balance					0
Contractual Principal Balance					0
Related Allowance					0
Average current balance		0		0
Impaired Financing Receivables With Related Allowance [Member] \| Installment
Financing Receivable, Impaired [Line Items]
Current balance					0
Contractual Principal Balance					0
Related Allowance					0
Average current balance		0		0
Impaired Financing Receivables With Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Current balance					11,719
Contractual Principal Balance					22,482
Related Allowance					$ 2,175
Average current balance		$ 8,228		$ 6,402