Loans Changes in Carrying Amount of Accretable Yield for Purchased Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended					3 Months Ended
Sep. 30, 2013 Covered Loans	Sep. 30, 2012 Covered Loans	Sep. 30, 2013 Covered Loans	Sep. 30, 2012 Covered Loans	Jun. 30, 2013 Covered Loans	Dec. 31, 2012 Covered Loans	Jun. 30, 2012 Covered Loans	Dec. 31, 2011 Covered Loans	Sep. 30, 2013 Acquired Impaired Acquired Loans	Apr. 12, 2013 Acquired Impaired Acquired Loans
Changes in Carrying Amount of Accretable Yield for Purchased Loans [Line Items]
Contractual required payments receivable	$ 811,319	$ 1,333,127	$ 811,319	$ 1,333,127					$ 907,626
Changes in the carrying amount of accretable yield for purchased loans [Roll Forward]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield	79,138	128,024	79,138	128,024	81,758	113,288	147,576	176,736	104,210	118,459
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Additions									0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	537,257	964,314	762,386	1,128,978						757,029
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion	14,056	23,631	51,327	75,478					(8,827)
Certain Loans Acquired in Transfer not Accounted for as Debt Securities Carrying Amount Accretion	14,056	23,631	51,327	75,478					8,827
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Reclassifications from Nonaccretable Difference	12,745	6,008	28,726	30,814
Certain Loans Acquired in Transfer not Accounted for as Debt Securities Carrying Amount Additions									0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities F D I C Payments Received under Loss Sharing Agreement	103,514	96,593	365,914	313,104					(92,536)
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Disposals of Loans	1,309	1,929	11,549	4,048					(5,422)
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	447,799	891,352	447,799	891,352					673,320	757,029
Nonaccretable difference	(284,382)	(313,751)	(284,382)	(313,751)					(130,096)
Expected cash flows	526,937	1,019,376	526,937	1,019,376					777,530
Accretable yield	$ (79,138)	$ (128,024)	$ (79,138)	$ (128,024)					$ (104,210)

CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesCarryingAmountAccretion.

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- Definition

Certain Loans Acquired in Transfer not Accounted for as Debt Securities Carrying Amount Additions

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Certain Loans Acquired In Transfer Not Accounted For As Debt Securities FDIC Payments Received Under Loss Sharing Agreement.

+ References

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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

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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.

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Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in 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

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Amount of decrease from accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of reduction, resulting from a sale or transfer of a loan, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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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.

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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.

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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.

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