Fair Value Measurements (Schedule Of Maturities On Debt Securities) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Less than 1 year	$ 6
1-5 years	468
5-10 years	219
More than 10 years	367
Total maturities of debt securities	$ 1,060

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

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