Investment Securities (Amortized Cost And Estimated Fair Value By Contractual Maturity Of Investment Securities Available For Sale) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	$ 7,545
1 to 5 Years, Amortized Cost	194,826
5 to 10 Years, Amortized Cost	1,959,205
More Than 10 years, Amortized Cost	924,464
No Stated Maturity, Amortized Cost	3,648
Total, Amortized Cost	3,089,688
Within One Year, Fair Value	7,660
1 to 5 Years, Fair Value	196,882
5 to 10 Years, Fair Value	1,938,287
More Than 10 years, Fair Value	929,924
No Stated Maturity, Fair Value	4,953
Total, Fair Value	3,077,706
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	357
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	0
More Than 10 years, Amortized Cost	0
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	357
Within One Year, Fair Value	357
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	0
More Than 10 years, Fair Value	0
No Stated Maturity, Fair Value	0
Total, Fair Value	357
U.S. Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	1,266
5 to 10 Years, Amortized Cost	31,757
More Than 10 years, Amortized Cost	2,026
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	35,049
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	1,392
5 to 10 Years, Fair Value	32,624
More Than 10 years, Fair Value	2,280
No Stated Maturity, Fair Value	0
Total, Fair Value	36,296
Securities Issued By U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	2,000
1 to 5 Years, Amortized Cost	184,489
5 to 10 Years, Amortized Cost	0
More Than 10 years, Amortized Cost	0
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	186,489
Within One Year, Fair Value	2,015
1 to 5 Years, Fair Value	186,072
5 to 10 Years, Fair Value	0
More Than 10 years, Fair Value	0
No Stated Maturity, Fair Value	0
Total, Fair Value	188,087
Mortgage-Backed Securities Issued By U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	1
1 to 5 Years, Amortized Cost	190
5 to 10 Years, Amortized Cost	287
More Than 10 years, Amortized Cost	208,523
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	209,001
Within One Year, Fair Value	1
1 to 5 Years, Fair Value	197
5 to 10 Years, Fair Value	298
More Than 10 years, Fair Value	209,065
No Stated Maturity, Fair Value	0
Total, Fair Value	209,561
Mortgage-Backed Securities Issued By U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	1,751
1 to 5 Years, Amortized Cost	4,982
5 to 10 Years, Amortized Cost	1,926,494
More Than 10 years, Amortized Cost	386,185
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	2,319,412
Within One Year, Fair Value	1,819
1 to 5 Years, Fair Value	5,256
5 to 10 Years, Fair Value	1,904,668
More Than 10 years, Fair Value	393,608
No Stated Maturity, Fair Value	0
Total, Fair Value	2,305,351
Collateralized Mortgage-Backed Securities Issued By U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	264
More Than 10 years, Amortized Cost	321,707
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	321,971
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	267
More Than 10 years, Fair Value	319,248
No Stated Maturity, Fair Value	0
Total, Fair Value	319,515
State And Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	3,436
1 to 5 Years, Amortized Cost	3,899
5 to 10 Years, Amortized Cost	403
More Than 10 years, Amortized Cost	3,023
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	10,761
Within One Year, Fair Value	3,468
1 to 5 Years, Fair Value	3,965
5 to 10 Years, Fair Value	430
More Than 10 years, Fair Value	3,161
No Stated Maturity, Fair Value	0
Total, Fair Value	11,024
Securities With No Stated Maturity (Equity Securities) [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	0
More Than 10 years, Amortized Cost	0
No Stated Maturity, Amortized Cost	3,648
Total, Amortized Cost	3,648
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	0
More Than 10 years, Fair Value	0
No Stated Maturity, Fair Value	4,953
Total, Fair Value	4,953
Other Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	0
More Than 10 years, Amortized Cost	3,000
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	3,000
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	0
More Than 10 years, Fair Value	2,562
No Stated Maturity, Fair Value	0
Total, Fair Value	$ 2,562