Investment Securities (Details 3) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Available For Sale Securities Debt Maturities Amortized Cost [Abstract]
Due within 1 year	$ 545
Due after 1 year through 5 years	358
Due after 5 years through 10 years	176
Due after 10 years	4,727
Total	5,806
Estimated Fair Value
Estimated Fair Value, Due within 1 year	549
Estimated Fair Value, Due after 1 year through 5 years	366
Estimated Fair Value, Due after 5 years through 10 years	187
Estimated Fair Value, Due after 10 years	4,881
Total	$ 5,983

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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This item represents the total of all debt securities grouped by maturity dates, 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 classified neither as held-to-maturity nor trading securities.

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This item represents the fair value of debt securities which are expected to mature within one year of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

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