Fair Value Measurements (Summary of Gains And Losses on Level 3 Assets and Liabilities) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Total gains or losses included in earnings	$ 2,600,000	$ (120,000)	$ 3,662,000	$ (2,749,000)
Change in unrealized gains or losses relating to assets still held	2,713,000	70,000	4,144,000	(2,541,000)
Other Non-Interest Income [Member]
Total gains or losses included in earnings	29,000.000	8,000.000	35,000.000	13,000.000
Change in unrealized gains or losses relating to assets still held	29,000.000	8,000.000	35,000.000	13,000.000
Loans Fees And Sales [Member]
Total gains or losses included in earnings	(34,000.000)	(103,000.000)	(403,000.000)	(121,000.000)
Change in unrealized gains or losses relating to assets still held	79,000.000	87,000.000	79,000.000	87,000.000
Investment Securities Gains Losses [Member]
Total gains or losses included in earnings	2,605,000.000	(25,000.000)	4,030,000.000	(2,641,000.000)
Change in unrealized gains or losses relating to assets still held	$ 2,605,000.000	$ (25,000.000)	$ 4,030,000.000	$ (2,641,000.000)