Investment Securities (Details 3) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Available For Sale Securities Debt Maturities Amortized Cost [Abstract]
Due within 1 year	$ 973
Due after 1 year through 5 years	421
Due after 5 years through 10 years	217
Due after 10 years	5,046
Total	6,657
Estimated Fair Value
Estimated Fair Value, Due within 1 year	983
Estimated Fair Value, Due after 1 year through 5 years	429
Estimated Fair Value, Due after 5 years through 10 years	227
Estimated Fair Value, Due after 10 years	5,094
Total	$ 6,733

This item represents debt securities, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are expected to mature after five years and through ten years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

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