Fair Value and Investment Securities Maturity Distribution Based on Contractual Terms of Investment Securities (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Available-For-Sale Amortized cost
Due within 1 year	$ 754
Due after 1 year through 5 years	770
Due after 5 years through 10 years	58
Due after 10 years	49
No contractual maturity	207
Total	1,838
Available-For-Sale Fair Value
Due within 1 year	754
Due after 1 year through 5 years	780
Due after 5 years through 10 years	59
Due after 10 years	45
No contractual maturity	206
Total	$ 1,844

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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