Fair Value Measurements (Schedule Of Maturities On Debt Securities) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014
Less than 1 year	$ 36
1-5 years	499
5-10 years	228
More than 10 years	355
Total maturities of debt securities	$ 1,118

Amount of available-for-sale debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at fair value maturing after the tenth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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