Loans And Leases (Recorded Investment In Loans And Leases) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Schedule Of Recorded Investment In Loans And Leases [Line Items]
Ending balance	$ 12,028,696	[1]	$ 11,225,404	[1]
Accrued interest	35,360		33,540
Total recorded investment	12,064,056		11,258,944
Total recorded investment: individually evaluated for impairment	428,121		495,276
Total recorded investment: collectively evaluated for impairment	11,635,935		10,763,668
Residential Mortgage [Member]
Schedule Of Recorded Investment In Loans And Leases [Line Items]
Ending balance	3,291,724	[1]	3,219,890	[1]
Accrued interest	10,271		10,992
Total recorded investment	3,301,995		3,230,882
Total recorded investment: individually evaluated for impairment	146,944		135,311
Total recorded investment: collectively evaluated for impairment	3,155,051		3,095,571
Consumer Loan [Member]
Schedule Of Recorded Investment In Loans And Leases [Line Items]
Ending balance	2,630,867	[1]	2,760,030	[1]
Accrued interest	8,095		8,777
Total recorded investment	2,638,962		2,768,807
Total recorded investment: individually evaluated for impairment	54,793		36,629
Total recorded investment: collectively evaluated for impairment	2,584,169		2,732,178
Commercial Loan [Member]
Schedule Of Recorded Investment In Loans And Leases [Line Items]
Ending balance	2,903,733	[1]	2,385,791	[1]
Accrued interest	9,453		6,585
Total recorded investment	2,913,186		2,392,376
Total recorded investment: individually evaluated for impairment	69,426		107,218
Total recorded investment: collectively evaluated for impairment	2,843,760		2,285,158
Commercial Real Estate [Member]
Schedule Of Recorded Investment In Loans And Leases [Line Items]
Ending balance	2,783,061	[1]	2,384,889	[1]
Accrued interest	7,541		7,186
Total recorded investment	2,790,602		2,392,075
Total recorded investment: individually evaluated for impairment	154,978		212,850
Total recorded investment: collectively evaluated for impairment	2,635,624		2,179,225
Financing [Member]
Schedule Of Recorded Investment In Loans And Leases [Line Items]
Ending balance	419,311	[1]	474,804	[1]
Accrued interest	0		0
Total recorded investment	419,311		474,804
Total recorded investment: individually evaluated for impairment	1,980		3,268
Total recorded investment: collectively evaluated for impairment	$ 417,331		$ 471,536

[1] The ending balance includes net deferred fees and unamortized premiums of $12.7 million and $20.6 million at December 31, 2012 and December 31, 2011, respectively.