Portfolio Loans Covered by Loss Share (Covered loans) - Rollforward of Covered Loans, Net of the Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 189,571	$ 298,975
Principal reductions and interest payments	(37,421)	(68,783)
Accretion of loan discount	19,987	22,231
Reclassifications from nonaccretable difference	5,841	1,894
Reductions due to disposals	(32,798)	(43,986)
Balance at end of period	145,180	210,331
Accretable Yield
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	78,768	63,335
Principal reductions and interest payments	0	0
Accretion of loan discount	(19,987)	(22,231)
Reclassifications from nonaccretable difference	14,233	67,178
Reductions due to disposals	(12,288)	(12,837)
Balance at end of period	60,726	95,445
Contractual Rights
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	386,966	618,791
Principal reductions and interest payments	(37,421)	(68,783)
Accretion of loan discount	0	0
Reclassifications from nonaccretable difference	9,216	1,671
Reductions due to disposals	(68,953)	(107,669)
Balance at end of period	289,808	444,010
Non-accretable difference
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	118,627	256,481
Principal reductions and interest payments	0	0
Accretion of loan discount	0	0
Reclassifications from nonaccretable difference	(10,858)	(67,401)
Reductions due to disposals	(23,867)	(50,846)
Balance at end of period	$ 83,902	$ 138,234

Principal reductions and interest payments

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- Details

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- Definition

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

-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)(2)

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

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

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.

+ References

+ Details

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