Covered Assets and FDIC Loss-sharing Asset (Changes in Accretable Yield for Acquired Loans) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011
Covered Assets And FDIC Loss Sharing Asset
Balance at beginning of period	$ 314,333	$ 256,572
Additions resulting from acquisitions	0	59,811
Accretion	(23,608)	(60,369)
Disposals	(8,594)	(24,134)
Reclassifications from nonaccretable difference	69	50,320
Balance at end of period	$ 282,200	$ 282,200

Covered Assets And FDIC Loss Sharing Asset [Abstract]

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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 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 AICPA

-Name Statement of Position (SOP)

-Number 03-3

-Paragraph 16

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: 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=6891207&loc=d3e13503-111538

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

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

+ Details

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- Definition

The current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. 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

+ Details

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- Definition

The increases in 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 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, due to the acquisition of similar loans not accounted for as debt securities during the period.

+ References

+ Details

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- Definition

The sale or transfer of a loan during the period resulting in a reduction in the excess of a loan's cash flows expected to be collected over the investor's initial investment. This relates to loans not accounted for as a debt security, with evidence of deterioration of credit quality since origination that was 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

+ Details

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- Definition

The change in the estimate of cash flows expected to be collected, after acquisition of loans, which results in an increase in accretable yield (for example, if actual cash flows are significantly greater than previously expected). This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was 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

+ Details

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