Long-Term Debt and Credit Facilities (Details 1) In Millions, unless otherwise specified	12 Months Ended					3 Months Ended	12 Months Ended	3 Months Ended		12 Months Ended
	Dec. 31, 2011 Three Year Notes at Point Six Percent [Member] USD ($)	Dec. 31, 2011 Five Year Notes at 1 Point 3 Percent [Member] USD ($)	Dec. 31, 2011 Ten Year Notes at 2 Point 45 Percent [Member] USD ($)	Dec. 31, 2011 Three Year Notes at 1 Point 25 Percent [Member] USD ($)	Dec. 31, 2011 Six Year Notes at 2 Point 625 Percent [Member] USD ($)	Dec. 31, 2010 Five Year Notes at 1 Point 375 Percent [Member] USD ($)	Dec. 31, 2010 Five Year Notes at 1 Point 375 Percent [Member] USD ($)	Dec. 31, 2010 Ten Year Notes at 2 Point 95 Percent [Member] USD ($)	Dec. 31, 2011 Euro Dominated Facility Agreement [Member] EUR (€)	Dec. 31, 2011 Domestic Revolving Credit Facility 1850 Million Capacity [Member] USD ($)	Dec. 31, 2011 Domestic Revolving Credit Facility 145 Million Capacity [Member] USD ($)
Schedule of U.S. dollar-denominated notes [Line Items]
Issuance date	fourth quarter of 2011			second quarter of 2011			fourth quarter of 2010
Face amount	$ 300	$ 400	$ 300	$ 250	$ 250	$ 188	$ 188	$ 250
Term of notes (in years)	three-year	five-year	ten-year	three-year	six-year	five-year		ten-year
Fixed Interest rate (in hundredths)	0.60%	1.30%	2.45%	1.25%	2.625%	1.375%	1.375%	2.95%
Line of Credit Facility, Expiration Date										November 2016	November 2012
Maximum borrowing capacity									€ 408	$ 1,850	$ 145