Investment Securities (Schedule Of Investments Within The Available For Sale Portfolio That Had Unrealized Losses) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	$ 1,079,055	$ 471,296
Less than 12 months, Unrealized Losses	(10,219)	(2,385)
12 months or longer, Fair Value	484,512	1,113,455
12 months or longer, Unrealized Losses	(12,991)	(33,328)
Total Fair Value	1,563,567	1,584,751
Total Unrealized Losses	(23,210)	(35,713)
Government Agency Issued Collateralized Mortgage Obligations ("CMO")
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	845,534	437,212
Less than 12 months, Unrealized Losses	(7,734)	(2,276)
12 months or longer, Fair Value	450,079	1,004,964
12 months or longer, Unrealized Losses	(11,967)	(31,789)
Total Fair Value	1,295,613	1,442,176
Total Unrealized Losses	(19,701)	(34,065)
Government Agency Issued Mortgage-Backed Securities ("MBS")
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	233,521	34,041
Less than 12 months, Unrealized Losses	(2,485)	(83)
12 months or longer, Fair Value	33,582	108,491
12 months or longer, Unrealized Losses	(784)	(1,539)
Total Fair Value	267,103	142,532
Total Unrealized Losses	(3,269)	(1,622)
Total debt securities
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	1,079,055	471,253
Less than 12 months, Unrealized Losses	(10,219)	(2,359)
12 months or longer, Fair Value	483,661	1,113,455
12 months or longer, Unrealized Losses	(12,751)	(33,328)
Total Fair Value	1,562,716	1,584,708
Total Unrealized Losses	(22,970)	(35,687)
Equity
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	0	43
Less than 12 months, Unrealized Losses	0	(26)
12 months or longer, Fair Value	851	0
12 months or longer, Unrealized Losses	(240)	0
Total Fair Value	851	43
Total Unrealized Losses	$ (240)	$ (26)