Loans, Allowance for Loan Losses, and Credit Quality (Details 2) (USD $) In Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	$ 476,813	$ 573,533
Provision for loan losses	47,000	390,010
Charge offs	(117,521)	(528,492)
Recoveries	19,669	41,762
Loans and Leases Receivable, Allowance, Ending Balance	425,961	476,813
Allowance for loan losses:
Ending balance impaired loans individually evaluated for impairment	54,980
Ending balance impaired loans collectively evaluated for impairment	72,730
Ending balance all other loans collectively evaluated for impairment	298,251
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	316,176
Ending balance impaired loans collectively evaluated for impairment	251,778
Ending balance all other loans collectively evaluated for impairment	12,521,635
Commercial Portfolio Segment [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	137,770
Provision for loan losses	19,193
Charge offs	(28,870)
Recoveries	10,530
Loans and Leases Receivable, Allowance, Ending Balance	138,623
Allowance for loan losses:
Ending balance impaired loans individually evaluated for impairment	8,305
Ending balance impaired loans collectively evaluated for impairment	12,304
Ending balance all other loans collectively evaluated for impairment	118,014
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	51,207
Ending balance impaired loans collectively evaluated for impairment	42,736
Ending balance all other loans collectively evaluated for impairment	3,108,358
Commercial Real Estate Portfolio Segment [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	165,584
Provision for loan losses	(12,739)
Charge offs	(19,934)
Recoveries	2,684
Loans and Leases Receivable, Allowance, Ending Balance	135,595
Allowance for loan losses:
Ending balance impaired loans individually evaluated for impairment	29,045
Ending balance impaired loans collectively evaluated for impairment	9,543
Ending balance all other loans collectively evaluated for impairment	97,007
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	164,163
Ending balance impaired loans collectively evaluated for impairment	65,523
Ending balance all other loans collectively evaluated for impairment	3,194,000
Real Estate Construction Portfolio Segment [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	56,772
Provision for loan losses	(6,969)
Charge offs	(21,920)
Recoveries	3,953
Loans and Leases Receivable, Allowance, Ending Balance	31,836
Allowance for loan losses:
Ending balance impaired loans individually evaluated for impairment	14,924
Ending balance impaired loans collectively evaluated for impairment	2,894
Ending balance all other loans collectively evaluated for impairment	14,018
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	63,801
Ending balance impaired loans collectively evaluated for impairment	19,687
Ending balance all other loans collectively evaluated for impairment	450,316
Finance Leases Portfolio Segment [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	7,396
Provision for loan losses	(5,200)
Charge offs	(112)
Recoveries	24
Loans and Leases Receivable, Allowance, Ending Balance	2,108
Allowance for loan losses:
Ending balance impaired loans collectively evaluated for impairment	49
Ending balance all other loans collectively evaluated for impairment	2,059
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	11,685
Ending balance impaired loans collectively evaluated for impairment	1,213
Ending balance all other loans collectively evaluated for impairment	41,103
Home Equity Portfolio Segments [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	55,090
Provision for loan losses	48,586
Charge offs	(23,896)
Recoveries	1,323
Loans and Leases Receivable, Allowance, Ending Balance	81,103
Allowance for loan losses:
Ending balance impaired loans individually evaluated for impairment	1,448
Ending balance impaired loans collectively evaluated for impairment	33,009
Ending balance all other loans collectively evaluated for impairment	46,646
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	9,854
Ending balance impaired loans collectively evaluated for impairment	48,376
Ending balance all other loans collectively evaluated for impairment	2,535,799
Installment Portfolio Segment [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	17,328
Provision for loan losses	4,742
Charge offs	(14,356)
Recoveries	1,022
Loans and Leases Receivable, Allowance, Ending Balance	8,736
Allowance for loan losses:
Ending balance impaired loans collectively evaluated for impairment	3,213
Ending balance all other loans collectively evaluated for impairment	5,523
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	3
Ending balance impaired loans collectively evaluated for impairment	4,738
Ending balance all other loans collectively evaluated for impairment	584,973
Residential Portfolio Segment [Member]
Changes in the allowance for loan losses by portfolio segment
Loans and Leases Receivable, Allowance, Beginning Balance	36,873
Provision for loan losses	(613)
Charge offs	(8,433)
Recoveries	133
Loans and Leases Receivable, Allowance, Ending Balance	27,690
Allowance for loan losses:
Ending balance impaired loans individually evaluated for impairment	1,258
Ending balance impaired loans collectively evaluated for impairment	11,718
Ending balance all other loans collectively evaluated for impairment	14,984
Loans [Abstract]
Ending balance impaired loans individually evaluated for impairment	15,463
Ending balance impaired loans collectively evaluated for impairment	69,505
Ending balance all other loans collectively evaluated for impairment	$ 2,607,086

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- Definition

Reflects the gross amount charged against earnings during the period as credit losses (bad debt expense) based on review of the loan and lease portfolio and application of the methodology for estimating credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-Publisher FASB
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-Paragraph 20
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section 50
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5212-111524

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- Definition

Reflects a reduction in bad debt expense attributable to collections of loans and lease receivables which had previously been fully or partially charged off as bad debts.

+ References

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- Definition

Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

+ References

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- Definition

The amount of the recorded investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, accounts receivable (with terms exceeding one year), notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Receivable
-URI http://asc.fasb.org/extlink&oid=6953735

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524
-Subparagraph (c)(1)

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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- Definition

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

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

The allowance for loan and lease losses represents the reserve to cover probable credit losses related to specifically identified loans and leases, as well as probable credit losses inherent in the remainder of the loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for loan losses in connection with business combinations determined to be appropriate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 8
-Subparagraph a(ii)
-Subsection I
-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 114
-Paragraph 20
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: 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(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 9
-Section 03
-Paragraph 7
-Subparagraph d

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 8, 9
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
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