Fair Value Accounting (Changes In Level 3 Fair Value Measurements) (Details) (USD $)	3 Months Ended						6 Months Ended
	Jun. 30, 2012		Mar. 31, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Investment Securities Available for Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfered assets			$ 501,000
Beginning balance	5,085,000		6,842,000		11,546,000		6,842,000		10,622,000
Included in earnings	0	[1]			0	[1]	(450,000)	[1]	1,000,000	[1]
Unrealized gains (losses) included in other comprehensive income	18,000				1,852,000		(788,000)		1,776,000
Change from consolidated to equity method investment	0				0		0		0
Purchases	0				0		0		0
Settlements	0				0		0		0
Transfers in and/or out of Level 3	0				0		(501,000)		0
Ending balance	5,103,000		5,085,000		13,398,000		5,103,000		13,398,000
The amount of total net gains (losses) for the year included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at March 31, 2012	0				0		(450,000)		1,000,000
Private Equity Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	22,568,000		21,418,000		20,198,000		21,418,000		47,357,000
Included in earnings	7,279,000	[1]			(301,000)	[1]	7,372,000	[1]	(169,000)	[1]
Unrealized gains (losses) included in other comprehensive income	0				0		0		0
Change from consolidated to equity method investment	0				0				(27,291,000)
Purchases	0				376		1,057,000	[2]	0	[2]
Settlements	0				0		0		0
Transfers in and/or out of Level 3	0				0		0		0
Ending balance	29,847,000				20,273,000		29,847,000		20,273,000
The amount of total net gains (losses) for the year included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at March 31, 2012	7,279,000				(301,000)		7,372,000		(169,000)
Other Derivative Contracts, Net [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers from Level 3 to Level 2			1,900,000
Beginning balance	(1,719,000)	[3]	(7,242,000)	[3]	5,475,000	[4]	(7,242,000)	[3]	5,470,000	[3]
Included in earnings	(1,734,000)	[1],[3]			(2,324,000)	[1],[4]	(4,713,000)	[1],[4]	(2,319,000)	[4]
Unrealized gains (losses) included in other comprehensive income	0	[3]			0	[4]	0	[3]	0	[3]
Change from consolidated to equity method investment	0	[3]			0		0		0	[4]
Purchases	0	[3]			0		0	[3]	0	[3]
Settlements	403,000	[3]			0		10,756,000		0	[4]
Transfers in and/or out of Level 3	0	[3]			0	[3]	(1,851,000)	[3]	0	[3]
Ending balance	(3,050,000)	[3]	(1,719,000)	[3]	3,151,000	[4]	(3,050,000)	[3]	3,151,000	[4]
The amount of total net gains (losses) for the year included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at March 31, 2012	$ (1,734,000)	[3]			$ (2,324,000)	[4]	$ (4,713,000)		$ (2,319,000)	[4]

[1] Included in earnings as a component of other non-interest income.

[2] Represents additional capital contributed to a private equity investment fund for capital calls.

[3] Other derivative contracts represent the Visa Derivative.

[4] Other derivative contracts include the Visa Derivative and the mortgage derivatives.