Fair Value Measurements (Schedule Of Individual Assets And The Related Total Losses) (Details) (USD $) In Thousands	3 Months Ended				9 Months Ended				12 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010		Dec. 31, 2010		Dec. 31, 2009
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans	$ 73		$ 17,437		$ 2,473		$ 58,761		$ 7,116		$ 91,009
Losses on loans held-for-sale			176				3,160		3,160		19,252
Losses on other real estate owned	4,125	[1]	(425)	[1]	6,505	[1]	1,739	[1]	20,139	[2]	28,216	[2]
Losses on investments in venture capital	50		231		337		553		760		1,982
Losses on equity investments	199				199				304
Total losses on assets	4,447		17,419		9,514		64,213		31,479		140,459
Commercial Loans [Member]
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans			2,642		1,868		4,079		3,411		16,293
Construction Loans- Residential [Member]
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans			1,009				4,635		1,295		23,234
Construction Loans- Other [Member]
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans			7,188				21,919				12,493
Real Estate Loans [Member]
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans			(127)		532		17,485		1,407		27,350
Land Loans [Member]
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans			6,638				9,728		1,003		11,639
Residential Mortgage Loans [Member]
Impaired Loans At Fair Value [Line Items]
Losses on impaired loans	$ 73		$ 87		$ 73		$ 915

[1] Other real estate owned balance of $94.3 million in the consolidated balance sheet is net of estimated disposal costs.

[2] Other real estate owned balance of $77.7 million in the consolidated balance sheet is net of estimated disposal costs.