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Accumulated Other Comprehensive Income (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income tax benefit in the accumulated net unrealized gain (loss) on other long-term liabilities
Balance, beginning of year	$ 1	$ 6	$ 2
Net unrealized losses (gains)	23	(5)	4
Balance, end of year	$ 24	$ 1	$ 6

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- Definition

Accumulated other comprehensive income other long term liabilities net of tax.

+ References

No definition available.

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- Definition

Other comprehensive income net unrealized Gain loss on other long term liabilities net of tax.

+ References

No definition available.

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