Investment Securities (Schedule of the Contractual Maturity of Debt Securities Available For Sale) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Investment Securities
Due within one year, amortized cost	$ 410,307
Due after one year through five years, amortized cost	1,993,459
Due after five years through ten years, amortized cost	2,450,596
Due after ten years, amortized cost	1,718,692
Mortgage and asset-backed securities, amortized cost	2,325,486
Total debt securities, amortized cost	8,898,540	8,175,981
Due within one year, fair value	412,900
Due after one year through five years, fair value	2,066,110
Due after five years through ten years, fair value	2,547,202
Due after ten years, fair value	1,770,311
Mortgage and asset-backed securities, fair value	2,406,133
Total debt securities, fair value	$ 9,202,656	$ 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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