Securities (Schedule Of Available For Sale Securities Unrealized Losses) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Available for sale securities, Losses less than 12 months, Fair Value	$ 2,223,768	$ 267,624
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	9,564	6,116
Available for sale securities, Losses 12 months or longer, Fair value	14,098	21,680
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	429	2,421
Available for sale securities, Total, Fair value	2,237,866	289,304
Available for sale securities, Total, Gross Unrealized Losses	9,993	8,537
U.S. Treasury [Member]
Available for sale securities, Losses less than 12 months, Fair Value		9,980
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses		5
Available for sale securities, Total, Fair value		9,980
Available for sale securities, Total, Gross Unrealized Losses		5
U.S. Government Agencies [Member]
Available for sale securities, Losses less than 12 months, Fair Value	117,917	74,566
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	802	434
Available for sale securities, Total, Fair value	117,917	74,566
Available for sale securities, Total, Gross Unrealized Losses	802	434
Municipal Obligations [Member]
Available for sale securities, Losses less than 12 months, Fair Value	75,975	57,713
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	210	3,092
Available for sale securities, Losses 12 months or longer, Fair value	12,515	19,870
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	325	2,319
Available for sale securities, Total, Fair value	88,490	77,583
Available for sale securities, Total, Gross Unrealized Losses	535	5,411
Mortgage-Backed Securities [Member]
Available for sale securities, Losses less than 12 months, Fair Value	1,508,442	122
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	6,253	1
Available for sale securities, Losses 12 months or longer, Fair value	1,253	1,340
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	61	49
Available for sale securities, Total, Fair value	1,509,695	1,462
Available for sale securities, Total, Gross Unrealized Losses	6,314	50
Collateralized Mortgage Obligations [Member]
Available for sale securities, Losses less than 12 months, Fair Value	518,953	122,312
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	2,220	2,491
Available for sale securities, Total, Fair value	518,953	122,312
Available for sale securities, Total, Gross Unrealized Losses	2,220	2,491
Other Debt Securities [Member]
Available for sale securities, Losses less than 12 months, Fair Value	56	379
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	1	6
Available for sale securities, Losses 12 months or longer, Fair value	316	459
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	23	37
Available for sale securities, Total, Fair value	372	838
Available for sale securities, Total, Gross Unrealized Losses	24	43
Equity Securities [Member]
Available for sale securities, Losses less than 12 months, Fair Value	2,425	2,552
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	78	87
Available for sale securities, Losses 12 months or longer, Fair value	14	11
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	20	16
Available for sale securities, Total, Fair value	2,439	2,563
Available for sale securities, Total, Gross Unrealized Losses	$ 98	$ 103