Loans and Allowance for Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified			12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended
Dec. 31, 2011 Legacy Loans [Member]	Dec. 31, 2010 Legacy Loans [Member]	Dec. 31, 2011 Noncovered Loans [Member]	Dec. 31, 2011 C & I [Member] Legacy Loans [Member]	Dec. 31, 2011 C & I [Member] Noncovered Loans [Member]	Dec. 31, 2011 CRE [Member] Legacy Loans [Member]	Dec. 31, 2011 CRE [Member] Noncovered Loans [Member]	Dec. 31, 2011 Construction [Member] Legacy Loans [Member]	Dec. 31, 2011 Construction [Member] Noncovered Loans [Member]	Dec. 31, 2011 Leases [Member] Legacy Loans [Member]	Dec. 31, 2011 Leases [Member] Noncovered Loans [Member]	Dec. 31, 2011 Installment [Member] Legacy Loans [Member]	Dec. 31, 2011 Installment [Member] Noncovered Loans [Member]	Dec. 31, 2011 Home Equity Lines [Member] Legacy Loans [Member]	Dec. 31, 2011 Home Equity Lines [Member] Noncovered Loans [Member]	Dec. 31, 2011 Credit cards [Member] Legacy Loans [Member]	Dec. 31, 2011 Credit cards [Member] Noncovered Loans [Member]	Dec. 31, 2011 Residential Mortgage [Member] Legacy Loans [Member]	Dec. 31, 2011 Residential Mortgage [Member] Noncovered Loans [Member]
Legacy Loans
Beginning Balance			$ 114,690		$ 29,764		$ 32,026		$ 7,180		$ 475		$ 21,555		$ 7,217		$ 11,107		$ 5,366
Charge-offs			(82,768)		(20,251)		(10,571)		(3,973)		(778)		(25,839)		(8,691)		(7,846)		(4,819)
Recoveries			21,742		2,162		630		685		37		13,639		1,985		2,264		340
Provision			54,035		20,688		9,772		1,281		607		8,626		6,255		1,844		4,962
Ending Balance			107,699		32,363		31,857		5,173		341		17,981		6,766		7,369		5,849
Loans
Ending Balance: Individually Evaluated	111,610		7,080	8,269	2,497	36,087	1,599	9,320	99	0	0	33,571	1,382	4,763	31	2,202	108	17,398	1,364
Ending Balance: Collectively Evaluated	7,524,166		100,619	2,740,433	29,866	1,956,106	30,258	268,015	5,074	73,530	341	1,227,574	16,599	719,928	6,735	144,154	7,261	394,426	4,485
Ending Balance	$ 7,635,776	$ 6,936,587	$ 107,699	$ 2,748,702	$ 32,363	$ 1,992,193	$ 31,857	$ 277,335	$ 5,173	$ 73,530	$ 341	$ 1,261,145	$ 17,981	$ 724,691	$ 6,766	$ 146,356	$ 7,369	$ 411,824	$ 5,849

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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

+ Details

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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

Charge to expense for financing receivables that are expected to be uncollectible.

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- Definition

Reduction to the allowance for credit losses related to collections on financing receivables which have been partially or fully charged off as bad debts.

+ References

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- Definition

Reduction to the allowance for credit losses related to financing receivables deemed uncollectible.

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- Definition

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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