Loans and Allowances for Credit Losses Part 2 (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	$ 11,093,254	$ 10,440,533
Individually measured for impairment, recorded investment	176,489	202,503
Total	11,269,743	10,643,036
Related allowance [Abstract]
Collectively measured for impairment, related allowance	201,355	259,103
Individually measured for impairment, related allowance	5,776	7,132
Total measured for impairment, related allowance	253,481	292,971	292,095
Allowance for loan losses [Roll Forward]
Beginning balance	292,971	292,095	273,236
Provision for (reduction of) allowance for loan losses	(1,040)	105,256	233,236
Loans charged off	(56,800)	(123,988)	(148,499)
Recoveries	18,350	19,608	10,680
Ending balance	253,481	292,971	292,095
Allowance for off-balance sheet credit losses [Abstract]
Beginning balance	14,271	14,388	15,166
Provision for (reduction of) off-balance sheet credit losses	(5,010)	(117)	(778)
Ending balance	9,261	14,271	14,388
Combined provision for (reduction of) allowances for credit losses	(6,050)	105,139	195,900
Commercial Portfolio Segment [Member]
Recorded investment [Abstract]
Total	6,571,454	5,933,996
Related allowance [Abstract]
Total measured for impairment, related allowance	83,443
Allowance for loan losses [Roll Forward]
Beginning balance	104,631
Provision for (reduction of) allowance for loan losses	(13,830)
Loans charged off	(14,836)
Recoveries	7,478
Ending balance	83,443
Allowance for off-balance sheet credit losses [Abstract]
Beginning balance	13,456
Provision for (reduction of) off-balance sheet credit losses	(5,550)
Ending balance	7,906
Combined provision for (reduction of) allowances for credit losses	(19,380)
Commercial Real Estate Portfolio Segment [Member]
Recorded investment [Abstract]
Total	2,279,909	2,277,350
Related allowance [Abstract]
Total measured for impairment, related allowance	67,034
Allowance for loan losses [Roll Forward]
Beginning balance	98,709
Provision for (reduction of) allowance for loan losses	(18,482)
Loans charged off	(15,973)
Recoveries	2,780
Ending balance	67,034
Allowance for off-balance sheet credit losses [Abstract]
Beginning balance	443
Provision for (reduction of) off-balance sheet credit losses	807
Ending balance	1,250
Combined provision for (reduction of) allowances for credit losses	(17,675)
Residential Portfolio Segment [Member]
Recorded investment [Abstract]
Total	1,970,461	1,828,248
Related allowance [Abstract]
Total measured for impairment, related allowance	39,207
Allowance for loan losses [Roll Forward]
Beginning balance	50,281
Provision for (reduction of) allowance for loan losses	699
Loans charged off	(14,107)
Recoveries	2,334
Ending balance	39,207
Allowance for off-balance sheet credit losses [Abstract]
Beginning balance	131
Provision for (reduction of) off-balance sheet credit losses	(40)
Ending balance	91
Combined provision for (reduction of) allowances for credit losses	659
Consumer Portfolio Segment [Member]
Recorded investment [Abstract]
Total	447,919	603,442
Related allowance [Abstract]
Total measured for impairment, related allowance	17,447
Allowance for loan losses [Roll Forward]
Beginning balance	12,614
Provision for (reduction of) allowance for loan losses	10,959
Loans charged off	(11,884)
Recoveries	5,758
Ending balance	17,447
Allowance for off-balance sheet credit losses [Abstract]
Beginning balance	241
Provision for (reduction of) off-balance sheet credit losses	(227)
Ending balance	14
Combined provision for (reduction of) allowances for credit losses	10,732
Commercial Portfolio Segment [Member]
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	6,502,696	5,895,674
Individually measured for impairment, recorded investment	68,759	38,322
Total	6,571,455	5,933,996
Related allowance [Abstract]
Collectively measured for impairment, related allowance	81,907	102,565
Individually measured for impairment, related allowance	1,536	2,066
Total measured for impairment, related allowance	83,443	104,631
Allowance for loan losses [Roll Forward]
Ending balance	83,443	104,631
Commercial Real Estate Portfolio Segment [Member]
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	2,180,716	2,126,984
Individually measured for impairment, recorded investment	99,193	150,366
Total	2,279,909	2,277,350
Related allowance [Abstract]
Collectively measured for impairment, related allowance	63,092	94,502
Individually measured for impairment, related allowance	3,942	4,207
Total measured for impairment, related allowance	67,034	98,709
Allowance for loan losses [Roll Forward]
Ending balance	67,034	98,709
Residential Portfolio Segment [Member]
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	1,963,020	1,816,184
Individually measured for impairment, recorded investment	7,441	12,064
Total	1,970,461	1,828,248
Related allowance [Abstract]
Collectively measured for impairment, related allowance	38,909	49,500
Individually measured for impairment, related allowance	298	781
Total measured for impairment, related allowance	39,207	50,281
Allowance for loan losses [Roll Forward]
Ending balance	39,207	50,281
Consumer Portfolio Segment [Member]
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	446,822	601,691
Individually measured for impairment, recorded investment	1,096	1,751
Total	447,918	603,442
Related allowance [Abstract]
Collectively measured for impairment, related allowance	17,447	12,536
Individually measured for impairment, related allowance	0	78
Total measured for impairment, related allowance	17,447	12,614
Allowance for loan losses [Roll Forward]
Ending balance	17,447	12,614
Segment Allocations [Member]
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	11,093,254	10,440,533
Individually measured for impairment, recorded investment	176,489	202,503
Total	11,269,743	10,643,036
Related allowance [Abstract]
Collectively measured for impairment, related allowance	201,355	259,103
Individually measured for impairment, related allowance	5,776	7,132
Total measured for impairment, related allowance	207,131	266,235
Allowance for loan losses [Roll Forward]
Ending balance	207,131	266,235
Unallocated Financing Receivables [Member]
Related allowance [Abstract]
Total measured for impairment, related allowance	46,350
Allowance for loan losses [Roll Forward]
Beginning balance	26,736
Provision for (reduction of) allowance for loan losses	19,614
Loans charged off	0
Recoveries	0
Ending balance	46,350
Allowance for off-balance sheet credit losses [Abstract]
Beginning balance	0
Provision for (reduction of) off-balance sheet credit losses	0
Ending balance	0
Combined provision for (reduction of) allowances for credit losses	$ 19,614

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

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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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Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, prior to deducting deferred income and the allowance for losses on loans and leases.

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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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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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