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LOANS AND LEASES - Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	$ 77,930		$ 77,930		$ 48,165
Current balance					59,600
Contractual Principal Balance					84,482
Related Allowance					2,175
Average current balance		$ 83,960		$ 84,250
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		7		124
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		513		1,428
Interest income recognized	753	520	1,593	1,552
Commercial
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	34,686		34,686		24,346
Current balance					27,480
Contractual Principal Balance					41,222
Related Allowance					2,044
Average current balance		42,151		38,839
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		1		87
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		316		807
Interest income recognized		317		894
Lease financing
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,092		1,092		223
Current balance					223
Contractual Principal Balance					223
Related Allowance					0
Average current balance		290		226
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		6		7
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	24,521		24,521		7,295
Current balance					10,831
Contractual Principal Balance					18,572
Related Allowance					113
Average current balance		19,713		22,414
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		4		27
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		94		295
Interest income recognized		98		322
Residential real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	12,104		12,104		10,892
Current balance					15,162
Contractual Principal Balance					17,662
Related Allowance					18
Average current balance		16,056		16,661
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		2		10
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		74		229
Interest income recognized		76		239
Home equity
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	5,374		5,374		5,242
Current balance					5,700
Contractual Principal Balance					6,462
Related Allowance					0
Average current balance		5,594		5,941
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		29		95
Interest income recognized		29		95
Installment
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	153		153		167
Current balance					204
Contractual Principal Balance					341
Related Allowance					0
Average current balance		150		162
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		0		2
Interest income recognized		0		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		77,824		78,975
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		37,835		35,626
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		148		155
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		6		7
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		18,703		20,907
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		15,388		16,177
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		5,594		5,941
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		150		162
Impaired Financing Receivables With Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Current balance	24,178		24,178
Impaired Financing Receivables With Related Allowance [Member] \| Commercial
Financing Receivable, Impaired [Line Items]
Current balance	21,632		21,632		10,754
Contractual Principal Balance					21,513
Related Allowance					2,044
Average current balance		4,316		3,213
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		142		71
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		1,010		1,507
Impaired Financing Receivables With Related Allowance [Member] \| Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance	$ 1,235		$ 1,235		294
Contractual Principal Balance					294
Related Allowance					18
Average current balance		668		484
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		$ 6,136		$ 5,275