Fair Value of Financial Assets and Liabilities Contractual Maturities of Investments (Detail) (Debt Securities, USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Debt Securities
Amortized Cost Basis
Due within one year	$ 1,897
Due after 1 year through 5 years	5,919
Due after 5 years through 10 years	557
Due after 10 years	447
Available For Sale Securities Amortized Cost	8,820	9,576
Aggregate Fair Value
Due within one year	1,900
Due after 1 year through 5 years	5,933
Due after 5 years through 10 years	574
Due after 10 years	444
Available For Sale Securities Fair Value	$ 8,851	$ 9,602

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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