Investment Securities (Schedule Of The Contractual Maturity Of Debt Securities Available For Sale) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Investment Securities
Due within one year, Amortized Cost	$ 513,749
Due after one year through five years, Amortized Cost	1,966,077
Due after five years through ten years, Amortized Cost	2,602,607
Due after ten years, Amortized Cost	1,793,100
Mortgage and asset-backed securities, Amortized Cost	2,237,473
Total debt securities, Amortized Cost	9,113,006	8,175,981
Due within one year, Fair Value	517,127
Due after one year through five years, Fair Value	2,029,429
Due after five years through ten years, Fair Value	2,729,133
Due after ten years, Fair Value	1,940,447
Mortgage and asset-backed securities, Fair Value	2,344,444
Total debt securities, Fair Value	$ 9,560,580	$ 8,372,439

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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