Investment Securities (Details 3) (USD $) In Millions	Sep. 30, 2011
Available For Sale Securities Debt Maturities Amortized Cost [Abstract]
Due within 1 year	$ 2,641
Due after 1 year through 5 years	728
Due after 5 years through 10 years	242
Due after 10 years	5,263
Total	8,874
Estimated Fair Value
Estimated Fair Value, Due within 1 year	2,649
Estimated Fair Value, Due after 1 year through 5 years	741
Estimated Fair Value, Due after 5 years through 10 years	253
Estimated Fair Value, Due after 10 years	5,255
Total	$ 8,898

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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