Loans, Allowance for Loan and Lease Losses, and Reserve for Off-Balance Sheet Credit Commitments (Details 3) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Allowance for Loan and Lease Losses
Beginning Balance	$ 265,933	$ 290,492	$ 257,007	$ 288,493
Provision for credit losses, net of transfers	7,999	13,000	6,203	100,000
Charge-offs	(15,172)	(34,587)	(29,613)	(121,176)
Recoveries	4,588	6,353	29,751	9,911
Net charge-offs (recoveries)	(10,584)	(28,234)	138	(111,265)
Ending Balance	263,348	274,167	263,348	274,167
Allowance individually evaluated for impairment	(18,933)		(18,933)
Allowance collectively evaluated for impairment	244,415		244,415
Loans and leases, excluding covered loans	12,164,209	11,418,625	12,164,209	11,418,625	11,386,628
Loans and leases, individually evaluated for impairment	158,475		158,475
Loans and leases, collectively evaluated for impairment	12,005,734		12,005,734
Provision for credit losses on loans and leases, excluding covered loans	7,500	13,000	7,500	100,000
Transfers to reserve for off-balance sheet credit commitments	(500)	1,091	1,300	3,061
Reserve for Off Balance Sheet Credit Commitments
Balance, beginning of period	23,325	19,310	21,529	17,340
Transfers (to) from allowance for loan and lease losses	(499)	1,091	1,297	3,061
Balance, end of period	22,826	20,401	22,826	20,401
Commercial (includes lease financing)
Allowance for Loan and Lease Losses
Beginning Balance	85,717		82,451
Provision for credit losses, net of transfers	2,772		5,359
Charge-offs	(6,282)	(20,100)	(12,966)	(60,850)
Recoveries	3,367	2,229	10,730	4,064
Net charge-offs (recoveries)	(2,915)		(2,236)
Ending Balance	85,574		85,574
Allowance individually evaluated for impairment	(14,364)		(14,364)
Allowance collectively evaluated for impairment	71,210		71,210
Loans and leases, excluding covered loans	5,166,802		5,166,802
Loans and leases, individually evaluated for impairment	32,489		32,489
Loans and leases, collectively evaluated for impairment	5,134,313		5,134,313
Commercial real estate mortgages
Allowance for Loan and Lease Losses
Beginning Balance	49,060		52,516
Provision for credit losses, net of transfers	(1,604)		(12,541)
Charge-offs	(1,231)	(9,105)	(4,127)	(24,556)
Recoveries	779	151	11,156	233
Net charge-offs (recoveries)	(452)		7,029
Ending Balance	47,004		47,004
Allowance individually evaluated for impairment	(1,375)		(1,375)
Allowance collectively evaluated for impairment	45,629		45,629
Loans and leases, excluding covered loans	2,059,114	1,967,959	2,059,114	1,967,959	1,958,317
Loans and leases, individually evaluated for impairment	25,898		25,898
Loans and leases, collectively evaluated for impairment	2,033,216		2,033,216
Residential mortgage
Allowance for Loan and Lease Losses
Beginning Balance	12,873		16,753
Provision for credit losses, net of transfers	(691)		(3,703)
Charge-offs	(245)	(604)	(1,267)	(2,684)
Recoveries	82	32	236	111
Net charge-offs (recoveries)	(163)		(1,031)
Ending Balance	12,019		12,019
Allowance individually evaluated for impairment	(130)		(130)
Allowance collectively evaluated for impairment	11,889		11,889
Loans and leases, excluding covered loans	3,742,768	3,586,858	3,742,768	3,586,858	3,552,312
Loans and leases, individually evaluated for impairment	10,226		10,226
Loans and leases, collectively evaluated for impairment	3,732,542		3,732,542
Real estate construction
Allowance for Loan and Lease Losses
Beginning Balance	29,455		40,824
Provision for credit losses, net of transfers	2,269		(13,503)
Charge-offs	(6,434)	(3,771)	(8,897)	(30,021)
Recoveries	201	3,810	7,067	4,933
Net charge-offs (recoveries)	(6,233)		(1,830)
Ending Balance	25,491		25,491
Allowance individually evaluated for impairment	(2,989)		(2,989)
Allowance collectively evaluated for impairment	22,502		22,502
Loans and leases, excluding covered loans	335,712	575,060	335,712	575,060	467,785
Loans and leases, individually evaluated for impairment	82,584		82,584
Loans and leases, collectively evaluated for impairment	253,128		253,128
Equity lines of credit
Allowance for Loan and Lease Losses
Beginning Balance	6,668		7,229
Provision for credit losses, net of transfers	(122)		194
Charge-offs	(523)	(807)	(1,443)	(1,363)
Recoveries	11	14	54	23
Net charge-offs (recoveries)	(512)		(1,389)
Ending Balance	6,034		6,034
Allowance individually evaluated for impairment	(75)		(75)
Allowance collectively evaluated for impairment	5,959		5,959
Loans and leases, excluding covered loans	728,890	757,210	728,890	757,210	733,741
Loans and leases, individually evaluated for impairment	6,630		6,630
Loans and leases, collectively evaluated for impairment	722,260		722,260
Installment loan
Allowance for Loan and Lease Losses
Beginning Balance	1,951		3,931
Provision for credit losses, net of transfers	417		(1,467)
Charge-offs	(457)	(200)	(913)	(1,702)
Recoveries	148	117	508	547
Net charge-offs (recoveries)	(309)		(405)
Ending Balance	2,059		2,059
Allowance collectively evaluated for impairment	2,059		2,059
Loans and leases, excluding covered loans	130,923	167,395	130,923	167,395	160,144
Loans and leases, individually evaluated for impairment	648		648
Loans and leases, collectively evaluated for impairment	130,275		130,275
Unallocated
Allowance for Loan and Lease Losses
Beginning Balance	80,209		53,303
Provision for credit losses, net of transfers	4,958		31,864
Ending Balance	85,167		85,167
Allowance collectively evaluated for impairment	$ 85,167		$ 85,167

Reflects the amount of loans and leases that have been removed or charged off from both loan receivables and the reserve for credit losses, net of any recoveries of previously removed or charged off credit losses.

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The sum of periodic provision charged to earnings, net of the transfer to or from the reserve for off-balance sheet credit commitments, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value.

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Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on loans and leases. Excludes loans covered by a loss sharing agreement with the Federal Deposit Insurance Corporation.

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Accrued liability to reflect exposure relating to off-balance sheet items such as commitments to extend credit, banker's acceptances and standby letters of credit.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Represents the amount of transfers from (to) the allowance for loan and lease losses.

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Represents the amount of transfers to (from) the reserve for off-balance sheet credit commitments.

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Reflects a reduction in bad debt expense attributable to collections of loans and lease receivables which had previously been fully or partially charged off as bad debts.

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Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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The valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The allowance for loan and lease losses represents the reserve to cover probable credit losses related to specifically identified loans and leases, as well as probable credit losses inherent in the remainder of the loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for loan losses in connection with business combinations determined to be appropriate.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The sum of the periodic provision charged to earnings, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value.

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