Investment Securities (Schedule Of Investments Within The Available For Sale Portfolio That Had Unrealized Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	$ 443,866	$ 1,782,008
Less than 12 months, Unrealized Losses	(1,969)	(47,083)
12 months or longer, Fair Value	519,915	77,904
12 months or longer, Unrealized Losses	(9,350)	(4,315)
Total Fair Value	963,781	1,859,912
Total Unrealized Losses	(11,319)	(51,398)
Government Agency Issued Collateralized Mortgage Obligations ("CMO")
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	417,267	1,637,064
Less than 12 months, Unrealized Losses	(1,729)	(43,221)
12 months or longer, Fair Value	485,053	77,904
12 months or longer, Unrealized Losses	(8,698)	(4,315)
Total Fair Value	902,320	1,714,968
Total Unrealized Losses	(10,427)	(47,536)
Government Agency Issued Mortgage-Backed Securities ("MBS")
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	25,712	144,901
Less than 12 months, Unrealized Losses	(79)	(3,839)
12 months or longer, Fair Value	34,853	0
12 months or longer, Unrealized Losses	(617)	0
Total Fair Value	60,565	144,901
Total Unrealized Losses	(696)	(3,839)
Total debt securities
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	442,979	1,781,965
Less than 12 months, Unrealized Losses	(1,808)	(47,060)
12 months or longer, Fair Value	519,906	77,904
12 months or longer, Unrealized Losses	(9,315)	(4,315)
Total Fair Value	962,885	1,859,869
Total Unrealized Losses	(11,123)	(51,375)
Equity
Schedule of Investments [Line Items]
Less than 12 months, Fair Value	887	43
Less than 12 months, Unrealized Losses	(161)	(23)
12 months or longer, Fair Value	9	0
12 months or longer, Unrealized Losses	(35)	0
Total Fair Value	896	43
Total Unrealized Losses	$ (196)	$ (23)