Loans and Leases (Information on How Loans and Leases were Modified as a TDR) (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		203	175	212
Post-Modification Recorded Investment | $		$ 37,636	$ 43,669	$ 49,215	[1]
Residential Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		16	17	27
Post-Modification Recorded Investment | $		$ 2,569	$ 2,801	$ 4,909	[1]
Residential Portfolio Segment [Member] | Adjusted Interest Rates [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		2	2	3
Post-Modification Recorded Investment | $		$ 335	$ 528	$ 573	[1]
Residential Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		12	13	26
Post-Modification Recorded Investment | $		$ 1,733	$ 1,537	$ 5,315	[1]
Residential Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		39	24	30	[2]
Post-Modification Recorded Investment | $		$ 6,200	$ 4,090	$ 4,366	[1],[2]
Consumer Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan				12
Post-Modification Recorded Investment | $	[1]			$ 1,012
Consumer Portfolio Segment [Member] | Adjusted Interest Rates [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		1	0	0
Post-Modification Recorded Investment | $		$ 247	$ 0	$ 0	[1]
Consumer Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan				12
Post-Modification Recorded Investment | $	[1]			$ 945
Consumer Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan	[2]			68
Post-Modification Recorded Investment | $	[1],[2]			$ 3,646
Commercial Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan				3
Post-Modification Recorded Investment | $	[1]			$ 254
Commercial Portfolio Segment [Member] | Adjusted Interest Rates [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		0	0	1
Post-Modification Recorded Investment | $		$ 0	$ 0	$ 24	[1]
Commercial Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan				7
Post-Modification Recorded Investment | $	[1]			$ 5,361
Commercial Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan	[2]			20
Post-Modification Recorded Investment | $	[1],[2]			$ 22,048
Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan				1
Post-Modification Recorded Investment | $	[1]			$ 315
Commercial Real Estate Portfolio Segment [Member] | Adjusted Interest Rates [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		0	1	0
Post-Modification Recorded Investment | $	[1]	$ 0	$ 237	$ 0
Commercial Real Estate Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan				1
Post-Modification Recorded Investment | $	[1]			$ 42
Commercial Real Estate Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan	[2]			1
Post-Modification Recorded Investment | $	[1],[2]			$ 405
Finance Leases Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		0	7	0
Post-Modification Recorded Investment | $		$ 0	$ 6,642	$ 0	[1]
Home Equity Loan [Member] | Consumer Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		12	11
Post-Modification Recorded Investment | $		$ 976	$ 484
Home Equity Loan [Member] | Consumer Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		14	15
Post-Modification Recorded Investment | $		$ 3,469	$ 1,156
Home Equity Loan [Member] | Consumer Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		73	52
Post-Modification Recorded Investment | $		$ 4,907	$ 3,131
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		0	3
Post-Modification Recorded Investment | $		$ 0	$ 4,921
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		0	2
Post-Modification Recorded Investment | $		$ 0	$ 335
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		0	1
Post-Modification Recorded Investment | $		$ 0	$ 509
Commercial and Industrial Sector [Member] | Commercial Portfolio Segment [Member] | Extended Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		12	12
Post-Modification Recorded Investment | $		$ 1,233	$ 14,883
Commercial and Industrial Sector [Member] | Commercial Portfolio Segment [Member] | Combination Rate and Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		18	2
Post-Modification Recorded Investment | $		$ 9,592	$ 648
Commercial and Industrial Sector [Member] | Commercial Portfolio Segment [Member] | other concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | loan		4	13
Post-Modification Recorded Investment | $		$ 6,375	$ 1,767

[1] Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs as a result of the restructurings was not significant.

[2] Other includes covenant modifications, forbearance, loans discharged under Chapter 7 bankruptcy, and/or other concessions.