Investment Securities (Expected Maturities Of Investment Securities Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2011
Investment Securities
Available-for-sale, Maturity within one year, Amortized Cost	$ 136,577
Available-for-sale, Maturity one to five years, Amortized Cost	1,187,875
Available-for-sale, Maturity five to ten years, Amortized Cost	244,519
Available-for-sale, Maturity beyond ten years, Amortized Cost	599,111
Available-for-sale, Amortized Cost	2,168,082
Held-to-maturity, Maturity within one year, Amortized Cost	4,200
Held-to-maturity, Maturity one to five years, Amortized Cost	103,160
Held-to-maturity, Maturity five to ten years, Amortized Cost	12,519
Held-to-maturity, Maturity beyond ten years, Amortized Cost	447,829
Held-to-maturity, Amortized Cost	567,708
Available-for-sale, Maturity within one year, Fair Value	138,767
Available-for-sale, Maturity one to five years, Fair Value	1,216,749
Available-for-sale, Maturity five to ten years, Fair Value	253,300
Available-for-sale, Maturity beyond ten years, Fair Value	594,039
Available-for-sale, Fair Value	2,202,855
Held-to-maturity, Maturity within one year, Fair Value	4,185
Held-to-maturity, Maturity one to five years, Fair Value	106,603
Held-to-maturity, Maturity five to ten years, Fair Value	12,767
Held-to-maturity, Maturity beyond ten years, Fair Value	450,619
Held-to-maturity, Fair Value	$ 574,174
Available-for-sale, Maturity within one year, Weighted Average Yield	2.91%
Available-for-sale, Maturity one to five years, Weighted Average Yield	2.75%
Available-for-sale, Maturity five to ten years, Weighted Average Yield	3.70%
Available-for-sale, Maturity beyond ten years, Weighted Average Yield	4.32%
Available-for-sale, Weighted Average Yield	3.30%
Held-to-maturity, Maturity within one year, Weighted Average Yield	1.52%
Held-to-maturity, Maturity one to five years, Weighted Average Yield	3.59%
Held-to-maturity, Maturity five to ten years, Weighted Average Yield	4.05%
Held-to-maturity, Maturity beyond ten years, Weighted Average Yield	3.91%
Held-to-maturity, Weighted Average Yield	3.84%

Available For Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield

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INVESTMENT SECURITIES

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