Loans, Allowance for Credit Losses, and Credit Quality Consumer Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Consumer Loans by credit quality indicator [Abstract]
Home equity	$ 1,014,465	$ 1,051,927
Installment and credit cards	425,729	454,219
Residential mortgage	5,682,178	5,056,891
Total consumer	7,122,372	6,563,037
Performing Financing Receivable [Member]
Consumer Loans by credit quality indicator [Abstract]
Home equity	985,087	1,017,604
Installment and credit cards	422,816	450,698
Residential mortgage	5,601,390	4,972,455
Total consumer	7,009,293	6,440,757
30 To 89 Days Past Due [Member]
Consumer Loans by credit quality indicator [Abstract]
Home equity	8,565	8,783
Installment and credit cards	1,723	1,932
Residential mortgage	4,811	4,846
Total consumer	15,099	15,561
Potential Problem [Member]
Consumer Loans by credit quality indicator [Abstract]
Home equity	227	880
Installment and credit cards	0	2
Residential mortgage	3,966	3,781
Total consumer	4,193	4,663
Impaired [Member]
Consumer Loans by credit quality indicator [Abstract]
Home equity	20,586	24,660
Installment and credit cards	1,190	1,587
Residential mortgage	72,011	75,809
Total consumer	$ 93,787	$ 102,056

Amount before allowance of consumer loans, including, but not limited to, mortgage, home equity, vehicles, credit card, installment, and lease financing. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a),(b))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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Amount before allowance of revolving, open-end loan, extended under a line of credit and secured by the borrower's residential property. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(3),(b))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount before allowance of installment and revolving loans issued to individuals, including, but not limited to credit card, automobile, boat, student, durable home appliance loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(4),(b))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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- Definition

Amount before allowance of consumer mortgage. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes subordinated loans such as home equity lines of credit and loans and leases covered under loss sharing agreements.

+ References

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