Parent Company Condensed Financial Information (Statements Of Financial Condition) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Apr. 29, 2010	Dec. 31, 2009
Cash and cash equivalents	$ 288,079				$ 229,889				$ 67,496		$ 118,847
Investment in subsidiary banks										25,000
Investment securities, available for sale	364,315				260,100
Other assets	51,430				64,245
Total	2,122,255	2,151,153	2,264,123	2,268,264	2,377,276	2,566,895	2,654,898	2,773,431	2,814,944
Subordinated debentures	81,963				81,963
Other liabilities	13,180				12,174
Preferred stock and related accounts					68,455
Common stock and related accounts	19,530				19,444
Total	2,122,255				2,377,276
Parent Company [Member]
Cash and cash equivalents	18,245				32,050				37,542		13,918
Investment in subsidiary banks	293,573				343,084
Investments in other subsidiaries	9,355				9,294
Investment securities, available for sale	2,462				1,986
Other assets	8,391				5,547
Total	332,026				391,961
Subordinated debentures	81,963				81,963
Other liabilities	4,007				8,409
Preferred stock and related accounts					68,455
Common stock and related accounts	246,056				233,134
Total	$ 332,026				$ 391,961