LOANS AND LEASES - Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 30,283		$ 24,082
Current balance	45,226		41,627
Contractual Principal Balance	52,163		47,857
Related Allowance	288		779
Average current balance	43,429	$ 55,544
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	11	26
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	193	342
Interest income recognized	204	368
Commercial
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	6,275		5,229
Current balance	8,810		7,331
Contractual Principal Balance	9,094		8,629
Related Allowance	100		169
Average current balance	8,071	16,701
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	13
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	26	109
Interest income recognized	26	122
Lease financing
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0		82
Current balance	0		82
Contractual Principal Balance	0		82
Related Allowance	0		0
Average current balance	41	149
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	1
Interest income recognized	0	1
Construction real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	26		29
Current balance	26		29
Contractual Principal Balance	58		60
Related Allowance	0		0
Average current balance	28	538
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	0
Interest income recognized	1	0
Commercial real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	16,878		10,616
Current balance	24,736		21,542
Contractual Principal Balance	29,230		23,957
Related Allowance	26		448
Average current balance	23,139	24,313
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	3	5
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	99	160
Interest income recognized	102	165
Residential real estate
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	3,324		4,140
Current balance	7,175		7,932
Contractual Principal Balance	8,327		9,208
Related Allowance	160		160
Average current balance	7,554	9,218
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	7	7
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	47	46
Interest income recognized	54	53
Home equity
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	3,484		3,743
Current balance	4,173		4,456
Contractual Principal Balance	4,985		5,499
Related Allowance	2		2
Average current balance	4,315	4,212
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	1	1
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	20	24
Interest income recognized	21	25
Installment
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	296		243
Current balance	306		255
Contractual Principal Balance	469		422
Related Allowance	0		0
Average current balance	281	413
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	43,482		37,183
Contractual Principal Balance	50,341		43,405
Related Allowance	0		0
Average current balance	40,334	48,790
Loans with no related allowance recorded [member] | Commercial
Financing Receivable, Impaired [Line Items]
Current balance	8,571		7,162
Contractual Principal Balance	8,777		8,460
Related Allowance	0		0
Average current balance	7,867	15,607
Loans with no related allowance recorded [member] | Lease financing
Financing Receivable, Impaired [Line Items]
Current balance	0		82
Contractual Principal Balance	0		82
Related Allowance	0		0
Average current balance	41	149
Loans with no related allowance recorded [member] | Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance	26		29
Contractual Principal Balance	58		60
Related Allowance	0		0
Average current balance	28	538
Loans with no related allowance recorded [member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance	24,377		18,423
Contractual Principal Balance	28,871		20,837
Related Allowance	0		0
Average current balance	21,400	19,939
Loans with no related allowance recorded [member] | Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance	6,130		6,876
Contractual Principal Balance	7,282		8,145
Related Allowance	0		0
Average current balance	6,503	8,033
Loans with no related allowance recorded [member] | Home equity
Financing Receivable, Impaired [Line Items]
Current balance	4,072		4,356
Contractual Principal Balance	4,884		5,399
Related Allowance	0		0
Average current balance	4,214	4,111
Loans with no related allowance recorded [member] | Installment
Financing Receivable, Impaired [Line Items]
Current balance	306		255
Contractual Principal Balance	469		422
Related Allowance	0		0
Average current balance	281	413
Impaired Financing Receivables With Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Current balance	1,744
Contractual Principal Balance	1,822
Related Allowance	288
Impaired Financing Receivables With Related Allowance [Member] | Commercial
Financing Receivable, Impaired [Line Items]
Current balance	239		169
Contractual Principal Balance	317		169
Related Allowance	100		169
Average current balance	204	1,094
Impaired Financing Receivables With Related Allowance [Member] | Lease financing
Financing Receivable, Impaired [Line Items]
Current balance	0		0
Contractual Principal Balance	0		0
Related Allowance	0		0
Average current balance	0	0
Impaired Financing Receivables With Related Allowance [Member] | Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance	0		0
Contractual Principal Balance	0		0
Related Allowance	0		0
Average current balance	0	0
Impaired Financing Receivables With Related Allowance [Member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance	359		3,119
Contractual Principal Balance	359		3,120
Related Allowance	26		448
Average current balance	1,739	4,374
Impaired Financing Receivables With Related Allowance [Member] | Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance	1,045		1,056
Contractual Principal Balance	1,045		1,063
Related Allowance	160		160
Average current balance	1,051	1,185
Impaired Financing Receivables With Related Allowance [Member] | Home equity
Financing Receivable, Impaired [Line Items]
Current balance	101		100
Contractual Principal Balance	101		100
Related Allowance	2		2
Average current balance	101	101
Impaired Financing Receivables With Related Allowance [Member] | Installment
Financing Receivable, Impaired [Line Items]
Current balance	0		0
Contractual Principal Balance	0		0
Related Allowance	0		0
Average current balance	0	0
Impaired Financing Receivables With Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Current balance			4,444
Contractual Principal Balance			4,452
Related Allowance			$ 779
Average current balance	$ 3,095	$ 6,754