Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended			6 Months Ended	1 Months Ended	6 Months Ended
	Nov. 30, 2010	Jun. 30, 2010 Income tax litigation	Jan. 31, 2011 Environmental Matters	Jun. 30, 2011 Environmental Matters	Nov. 30, 2009 Potential Securities Class Action	Jun. 30, 2011 Potential Securities Class Action	Jun. 30, 2011 Other
Commitments and contingencies
Extension of time to submit the proposed final order (in days)	90
Number of days to respond to audit findings by the Internal Revenue Service (in days)		30
Number of cases into which ruling are consolidated				1
Number of environmental interest groups filing Clean Water Act citizen's suit			3
Number of non-executive directors as defendants					2
General damages entitled to recover						$ 200
Punitive damages entitled to recover						20
Undistributed Foreign Earnings							$ 10