Loans, Allowance for Loan and Lease Losses, and Reserve for Off-Balance Sheet Credit Commitments (Details 3) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Changes in Accretable Yield for Acquired Impaired Loans
Balance at the beginning of the period	$ 219,018	$ 295,813
Accretion	(24,907)	(33,221)
Reclassifications from nonaccretable difference	18,965	15,978
Disposals and other	(16,198)	(24,605)
Balance at the end of the period	196,878	253,965
Acquired loans
FDIC indemnification asset	$ 68,038		$ 89,227
Charge off of consumer loans, delinquency period for overdrafts, low end of range	60 days
Charge off of consumer loans, delinquency period for secured consumer loans	180 days

Represents the low end of range for the charge off of consumer loans, which is the delinquency period for overdrafts.

No definition available.

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- Definition

Represents the high end of range for the charge off of consumer loans, which is the delinquency period for secured consumer loans.

+ References

No definition available.

+ 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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Balance Type:	credit
Period Type:	duration

- 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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- Details

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- Definition

Amount of decrease from reclassification to nonaccretable difference 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

Name:	us-gaap_CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToNonaccretableDifference
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Details

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- Definition

Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant