Investment Securities (Held To Maturity Securities Age Of Unrealized Losses And Fair Value Of Related Securities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 598,837		$ 1,014,006
Gross Unrealized Gains	17,428		42,248
Gross Unrealized Losses	(49,745)		(20,972)
Fair Value	566,520		1,035,282
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			162,404
Gross Unrealized Gains			1,406
Fair Value			163,810
U.S. Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	89,787		88,926
Gross Unrealized Gains	1,204		26
Gross Unrealized Losses	(243)		(152)
Fair Value	90,748		88,800
Obligations Of States And Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	18,893		28,231
Gross Unrealized Gains	1,322		1,234
Gross Unrealized Losses	(1)		(3)
Fair Value	20,214		29,462
Residential Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	304,631		578,282
Gross Unrealized Gains	10,950		35,016
Gross Unrealized Losses	(5,444)		(2,940)
Fair Value	310,137		610,358
Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	96,956	[1]	54,060	[1]
Gross Unrealized Gains	78	[1]	1,142	[1]
Gross Unrealized Losses	(33,176)	[1]	(14,119)	[1]
Fair Value	63,858	[1]	41,083	[1]
Corporate And Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	40,638		53,379
Gross Unrealized Gains	2,554		2,612
Gross Unrealized Losses	(3,582)		(2,030)
Fair Value	39,610		53,961
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	47,932		48,724
Gross Unrealized Gains	1,320		812
Gross Unrealized Losses	(7,299)		(1,728)
Fair Value	$ 41,953		$ 47,808

[1] Includes three pooled trust preferred securities, principally collateralized by securities issued by banks and insurance companies.