Long-Term Investments - Long-term investments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Equity Method Investments [Line Items]
Equity-method investments	$ 106	$ 94
Cost-method investments	13	27
Total	$ 119	$ 121

This element represents the aggregate carrying amount of all cost-method investments held by the Company. Generally, such investments do not have readily determinable fair values and are not required to be accounted for by the equity method. The carrying amount of such securities equates to cost, adjusted for other-than-temporary impairment. The cost method and lower-of-cost or market, an adaptation of the cost method, is generally followed for most investments in noncontrolled corporations, in some corporate joint ventures, and to a lesser extent in unconsolidated subsidiaries, particularly foreign.

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