Loans Changes in Carrying Amount of Accretable Yield for Purchased Loans at Acquisition Date (Details) (USD $) In Thousands, unless otherwise specified	Apr. 12, 2013
Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	$ 824,608
Contractual required payments receivable	1,086,503
Nonaccretable difference	(130,096)
Expected cash flows	956,407
Accretable yield	(131,799)
Carrying balance	824,608
Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	3,799,685
Contractual required payments receivable	4,020,812
Nonaccretable difference	0
Expected cash flows	4,020,812
Accretable yield	(221,127)
Carrying balance	3,799,685
Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	4,624,293
Contractual required payments receivable	5,107,315
Nonaccretable difference	(130,096)
Expected cash flows	4,977,219
Accretable yield	(352,926)
Carrying balance	4,624,293
Commercial Loan \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	488,626
Commercial Loan \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	2,041,113
Commercial Loan \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	2,529,739
Consumer Loan \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	335,982
Consumer Loan \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	1,758,572
Consumer Loan \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	2,094,554
Commercial and Industrial Financing Receivable \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	95,188
Commercial and Industrial Financing Receivable \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	1,664,912
Commercial and Industrial Financing Receivable \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	1,760,100
Commercial Real Estate Other Receivable \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	380,039
Commercial Real Estate Other Receivable \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	359,066
Commercial Real Estate Other Receivable \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	739,105
Construction \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	13,399
Construction \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	17,135
Construction \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	30,534
Residential mortgages \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	233,007
Residential mortgages \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	279,736
Residential mortgages \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	512,743
Consumer Installment Financing Receivable \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	54,377
Consumer Installment Financing Receivable \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	1,165,235
Consumer Installment Financing Receivable \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	1,219,612
Consumer Home Equity Lines Financing Receivable \| Acquired Impaired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	48,598
Consumer Home Equity Lines Financing Receivable \| Acquired performing loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	313,601
Consumer Home Equity Lines Financing Receivable \| Acquired Loans
Reconciliaiton of carrying amount of acquired loans [Line Items]
Loans	$ 362,199

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For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

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- Definition

The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

No definition available.

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- Definition

The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

No definition available.

+ Details

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- Definition

Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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