Fair Value Of Assets And Liabilities (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	$ 223,158		$ 222,687
Total securities available-for-sale	3,098,492		2,887,112
Mortgage servicing rights	142,956	144,069	207,748	207,319
Total other assets	364,439		282,031
Total assets	5,067,086		4,524,432
Total trading liabilities - capital markets	567,571		384,250
Other short-term borrowings	15,073		27,991
Total other liabilities	234,188		194,557
Total liabilities	816,832		606,798
Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	13,794		13,792
Total other assets	56,493		39,497
Total assets	70,287		53,289
Total other liabilities	10,538		23,251
Total liabilities	10,538		23,251
Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	8,555		12,824
Total securities available-for-sale	3,065,925		2,851,713
Total other assets	307,946		242,534
Total assets	4,603,081		4,006,555
Total trading liabilities - capital markets	567,571		384,250
Total other liabilities	220,690		169,206
Total liabilities	788,261		553,456
Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	214,603		209,863
Total securities available-for-sale	18,773		21,607
Mortgage servicing rights	142,956		207,748
Total assets	393,718		464,588
Other short-term borrowings	15,073		27,991
Total other liabilities	2,960		2,100
Total liabilities	18,033		30,091
U.S. Treasuries [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	40,037		60,322
Total trading liabilities - capital markets	445,381		245,541
U.S. Treasuries [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	40,037		60,322
Total trading liabilities - capital markets	445,381		245,541
Government Agency Issued Mortgage-Backed Securities ("MBS") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	1,427,029		1,542,229
Total trading liabilities - capital markets			335
Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	1,427,029		1,542,229
Total trading liabilities - capital markets			335
Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	1,572,836		1,208,752
Total trading liabilities - capital markets			12,454
Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	1,572,836		1,208,752
Total trading liabilities - capital markets			12,454
Other U.S. Government Agencies [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	14,547		21,125
Total trading liabilities - capital markets	1,822		995
Other U.S. Government Agencies [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	9,453		14,197
Total trading liabilities - capital markets	1,822		995
Other U.S. Government Agencies [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	5,094		6,928
States And Municipalities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	18,070		26,015
Total trading liabilities - capital markets	181		842
States And Municipalities [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	16,570		24,515
Total trading liabilities - capital markets	181		842
States And Municipalities [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	1,500		1,500
Corporate And Other Debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	527		543
Total trading liabilities - capital markets	120,088		124,083
Corporate And Other Debt [Member] | Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	527		543
Corporate And Other Debt [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total trading liabilities - capital markets	120,088		124,083
Venture Capital Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	12,179		13,179
Venture Capital Investments [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	12,179		13,179
Equity, Mutual Funds, And Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	13,267		14,947
Equity, Mutual Funds, And Other [Member] | Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale	13,267		13,249
Equity, Mutual Funds, And Other [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total securities available-for-sale			1,698
Other Trading Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total trading liabilities - capital markets	99
Other Trading Liabilities [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total trading liabilities - capital markets	99
Deferred Compensation Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	24,102		25,281
Deferred Compensation Assets [Member] | Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	24,102		25,281
Derivatives, Forwards And Futures [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	32,391		14,216
Total other liabilities	10,538		23,251
Derivatives, Forwards And Futures [Member] | Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	32,391		14,216
Total other liabilities	10,538		23,251
Derivatives, Interest Rate Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	307,946		242,534
Total other liabilities	220,686		169,206
Derivatives, Interest Rate Contracts [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	307,946		242,534
Total other liabilities	220,686		169,206
Derivatives, Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	2,964		2,100
Derivatives, Other [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	4
Derivatives, Other [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	2,960		2,100
Capital Markets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,213,431		890,727
Capital Markets [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,213,426		890,693
Capital Markets [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	5		34
Capital Markets [Member] | U.S. Treasuries [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	106,317		78,759
Capital Markets [Member] | U.S. Treasuries [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	106,317		78,759
Capital Markets [Member] | Government Agency Issued Mortgage-Backed Securities ("MBS") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	435,924		405,895
Capital Markets [Member] | Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	435,924		405,895
Capital Markets [Member] | Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	190,244		69,387
Capital Markets [Member] | Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	190,244		69,387
Capital Markets [Member] | Other U.S. Government Agencies [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	183,718		22,350
Capital Markets [Member] | Other U.S. Government Agencies [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	183,718		22,350
Capital Markets [Member] | States And Municipalities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	33,481		17,599
Capital Markets [Member] | States And Municipalities [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	33,481		17,599
Capital Markets [Member] | Corporate And Other Debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	263,303		296,586
Capital Markets [Member] | Corporate And Other Debt [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	263,298		296,552
Capital Markets [Member] | Corporate And Other Debt [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	5		34
Capital Markets [Member] | Equity, Mutual Funds, And Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	444		151
Capital Markets [Member] | Equity, Mutual Funds, And Other [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	444		151
Mortgage Banking [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	24,610		34,127
Mortgage Banking [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	7,229		8,791
Mortgage Banking [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	17,381		25,336
Mortgage Banking [Member] | Certificated Principal Only [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	7,229		8,791
Mortgage Banking [Member] | Certificated Principal Only [Member] | Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	7,229		8,791
Mortgage Banking [Member] | Interest Only Trading Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	17,381		25,336
Mortgage Banking [Member] | Interest Only Trading Securities [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	$ 17,381		$ 25,336