Allowance for Loan Losses (Impaired Financing Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			$ 11,128
Credit Card Receivable
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			243
Residential Mortgages
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			944
Commercial and Industrial
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			6,052
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			2,554
Construction Loans
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			0
Installment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			1,054
Home Equity Line of Credit
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance			281
Originated Loans
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 66,032		50,141
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	76,978		57,809
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	58,311		55,051
Impaired Financing Receivable, with Related Allowance, Recorded Investment	76,623		78,897
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	77,026		85,211
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	9,290	$ 13,297	14,349
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	68,869		62,887
Impaired Financing Receivable, Recorded Investment	142,655	110,943	129,038
Impaired Financing Receivable, Unpaid Principal Balance	154,004	127,631	143,020
Impaired Financing Receivable, Related Allowance	9,290	13,297	14,349
Impaired Financing Receivable, Average Recorded Investment	127,180	105,804	117,938
Originated Loans \| Credit Card Receivable
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	13	21	21
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	13	21	21
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	20	23	20
Impaired Financing Receivable, with Related Allowance, Recorded Investment	674	794	696
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	674	794	696
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	225	263	243
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	725	823	757
Originated Loans \| Residential Mortgages
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	11,184		11,550
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	13,562		13,901
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	11,775		11,979
Impaired Financing Receivable, with Related Allowance, Recorded Investment	11,921		12,355
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	12,036		12,458
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1,038	1,416	944
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	12,394		12,619
Originated Loans \| Residential Portfolio Segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		12,424
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		15,125
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		12,488
Impaired Financing Receivable, with Related Allowance, Recorded Investment		12,398
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		12,487
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		1,416
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		12,414
Originated Loans \| Commercial and Industrial
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	32,520	28,513	21,066
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	38,568	35,307	23,854
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	30,827	25,006	27,215
Impaired Financing Receivable, with Related Allowance, Recorded Investment	14,476	7,279	22,752
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	14,617	7,350	28,881
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	6,194	10,042	11,837
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	14,117	5,984	11,284
Originated Loans \| Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	20,598	9,343	15,465
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	22,604	15,478	17,456
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	13,776	9,634	13,031
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,415	5,657	1,149
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	3,447	5,664	1,173
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	567	317	128
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	2,435	5,668	3,037
Originated Loans \| Construction Loans
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	0	0	0
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	0	0
Originated Loans \| Finance Leases Portfolio Segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	0
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0
Originated Loans \| Home equity lines
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		977
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		1,222
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		987
Impaired Financing Receivable, with Related Allowance, Recorded Investment		6,655
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		6,655
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		254
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		6,715
Originated Loans \| Total impaired loans with no related allowance
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		53,124
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		69,581
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		50,019
Originated Loans \| Total impaired loans with a related allowance
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		57,819
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		58,050
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		13,297
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		55,785
Originated Loans \| Installment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,236	1,846	1,369
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	1,493	2,428	1,658
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1,162	1,881	1,807
Impaired Financing Receivable, with Related Allowance, Recorded Investment	38,898	25,036	35,535
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	39,013	25,100	35,592
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1,081	1,005	1,009
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	32,499	24,181	28,808
Originated Loans \| Home Equity Line of Credit
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	481		670
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	738		919
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	751		999
Impaired Financing Receivable, with Related Allowance, Recorded Investment	7,239		6,410
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	7,239		6,411
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	185	$ 254	188
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	$ 6,699		$ 6,382

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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