Investment Securities (Details 2) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010
Expected remaining maturities of debt securities available-for-sale, fair value
Fair Value	$ 6,348,055	$ 5,720,675	$ 4,761,143
Total debt securities
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	1,645,921
Over 1 year through 5 years, fair value	3,369,784
Over 5 years through 10 years, fair value	1,170,879
Over 10 years, fair value	155,359
Fair Value	6,341,943	5,710,239	4,749,588
Expected remaining maturities of debt securities available-for-sale, amortized cost
One year or less, amortized cost	1,640,997
Over 1 year through 5 years, amortized cost	3,291,398
Over 5 years through 10 years, amortized cost	1,161,517
Over 10 years, amortized cost	154,759
Total of debt securities available-for-sale, amortized cost	6,248,671
U.S. Treasury
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	10,072
Over 1 year through 5 years, fair value	3,004
Fair Value	13,076	14,113	19,145
Federal agency - Debt
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	1,258,008
Over 1 year through 5 years, fair value	525,285
Over 5 years through 10 years, fair value	63,939
Fair Value	1,847,232	1,142,328	1,090,846
Federal agency - MBS
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	45
Over 1 year through 5 years, fair value	198,026
Over 5 years through 10 years, fair value	288,692
Over 10 years, fair value	47,963
Fair Value	534,726	551,346	466,713
CMOs - Federal agency
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	319,152
Over 1 year through 5 years, fair value	2,416,854
Over 5 years through 10 years, fair value	665,121
Over 10 years, fair value	52,774
Fair Value	3,453,901	3,497,147	2,528,237
CMOs - Non-agency
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	11,569
Over 1 year through 5 years, fair value	41,943
Over 5 years through 10 years, fair value	37,571
Fair Value	91,083	118,295	217,078
State and municipal
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	42,026
Over 1 year through 5 years, fair value	168,958
Over 5 years through 10 years, fair value	92,198
Over 10 years, fair value	54,622
Fair Value	357,804	343,380	360,422
Other debt securities
Expected remaining maturities of debt securities available-for-sale, fair value
One year or less fair value	5,049
Over 1 year through 5 years, fair value	15,714
Over 5 years through 10 years, fair value	23,358
Fair Value	$ 44,121	$ 43,630	$ 67,147

For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading.

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