Principles Of Consolidation And Other Matters (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Equity method gains (losses)		$ (4)		$ 14	$ 13
Equity method investments	84			84
Remaining capital commitment	67			67
Effective tax rate	32.80%	30.00%		30.40%	20.80%
Gross unrecognized tax benefits	154			154		199
Settlement agreement, recognized charge after insurance			400
Minimum [Member] | Significant Change in Unrecognized Tax Benefits is Reasonably Possible Estimated Range of Change Upper Limit [Member]
Projection of unrecognized tax benefit in twelve months, lower bound	0			0
Maximum [Member] | Significant Change in Unrecognized Tax Benefits is Reasonably Possible Estimated Range of Change Upper Limit [Member]
Projection of unrecognized tax benefit in twelve months, upper bound	80			80
Covered by Insurance [Member]
Settlement agreement			100
Excluding Tax Benefit [Member]
Effective tax rate					29.60%
Mercer [Member]
Settlement agreement			$ 500