Investment Securities (Schedule Of Unrealized Loss On Investments) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	$ 247,109	$ 2,291,995
Less than 12 Months, Unrealized Losses	797	43,983
12 Months or Longer, Fair Value	1,253,241	4,713
12 Months or Longer, Unrealized Losses	23,293	578
Total Fair Value, Fair Value	1,500,350	2,296,708
Total Fair Value, Unrealized Losses	24,090	44,561
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Unrealized Losses	0	0
12 Months or Longer, Fair Value	0	0
12 Months or Longer, Unrealized Losses	0	0
Total Fair Value, Fair Value	0	0
Total Fair Value, Unrealized Losses	0	0
U.S. Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Unrealized Losses	0	0
12 Months or Longer, Fair Value	0	0
12 Months or Longer, Unrealized Losses	0	0
Total Fair Value, Fair Value	0	0
Total Fair Value, Unrealized Losses	0	0
Securities Issued By U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Unrealized Losses	0	0
12 Months or Longer, Fair Value	0	0
12 Months or Longer, Unrealized Losses	0	0
Total Fair Value, Fair Value	0	0
Total Fair Value, Unrealized Losses	0	0
Mortgage-Backed Securities Issued By U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	9,678	121,607
Less than 12 Months, Unrealized Losses	14	3,363
12 Months or Longer, Fair Value	29,955	2,951
12 Months or Longer, Unrealized Losses	919	298
Total Fair Value, Fair Value	39,633	124,558
Total Fair Value, Unrealized Losses	933	3,661
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	220,542	1,885,521
Less than 12 Months, Unrealized Losses	562	31,640
12 Months or Longer, Fair Value	1,099,220	0
12 Months or Longer, Unrealized Losses	19,907	0
Total Fair Value, Fair Value	1,319,762	1,885,521
Total Fair Value, Unrealized Losses	20,469	31,640
Collateralized Mortgage Obligations Issued By U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	282,898
Less than 12 Months, Unrealized Losses	0	8,875
12 Months or Longer, Fair Value	122,239	0
12 Months or Longer, Unrealized Losses	2,249	0
Total Fair Value, Fair Value	122,239	282,898
Total Fair Value, Unrealized Losses	2,249	8,875
State And Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Unrealized Losses	0	0
12 Months or Longer, Fair Value	43	40
12 Months or Longer, Unrealized Losses	2	2
Total Fair Value, Fair Value	43	40
Total Fair Value, Unrealized Losses	2	2
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Unrealized Losses	0	0
12 Months or Longer, Fair Value	0	0
12 Months or Longer, Unrealized Losses	0	0
Total Fair Value, Fair Value	0	0
Total Fair Value, Unrealized Losses	0	0
Other Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	16,889	1,969
Less than 12 Months, Unrealized Losses	221	105
12 Months or Longer, Fair Value	1,784	1,722
12 Months or Longer, Unrealized Losses	216	278
Total Fair Value, Fair Value	18,673	3,691
Total Fair Value, Unrealized Losses	$ 437	$ 383