Debt and Financing Arrangements Financing Arrangements (Details)	3 Months Ended						3 Months Ended								3 Months Ended
	Sep. 30, 2013 EUR (€)	Dec. 31, 2011 USD ($)	Sep. 30, 2013 50 million Euro revolving credit facility EUR (€) CreditFacility	Sep. 30, 2013 37 million Euro revolving credit facility EUR (€)	Sep. 30, 2013 50 million revolving credit facility USD ($)	Sep. 30, 2013 100 million Euro revolving credit facility EUR (€)	Dec. 31, 2012 Floating rate credit facility EUR (€)	Dec. 31, 2011 Floating rate credit facility EUR (€)	Sep. 30, 2013 4.875 % Due in 2013 USD ($)	Sep. 30, 2012 4.875 % Due in 2013 USD ($)	Dec. 31, 2012 Revolving Credit Facility Expired in December 2012 USD ($)	Dec. 31, 2012 Revolving Credit Facility Expired in December 2012 Credit Facilities USD ($)	Dec. 31, 2012 Committed Revolving Credit Facility Expiring in November 2013 USD ($)	Dec. 31, 2012 Committed Revolving Credit Facility Expiring in December 2013 USD ($)	Dec. 31, 2012 Senior Unsecured Fixed Rate Notes Due 2012 USD ($)	Mar. 31, 2012 11.5 % Due in 2042 USD ($)	Sep. 30, 2013 2.355 % Due in 2017 USD ($)	Sep. 30, 2012 2.355 % Due in 2017 USD ($)	Mar. 31, 2012 2.355 % Due in 2017 USD ($)	Sep. 30, 2013 2.6 % Due in 2017 USD ($)	Sep. 30, 2012 2.6 % Due in 2017 USD ($)	Dec. 31, 2011 2.6 % Due in 2017 USD ($)	Sep. 30, 2013 3.75 % Due in 2022 USD ($)	Sep. 30, 2012 3.75 % Due in 2022 USD ($)	Dec. 31, 2011 3.75 % Due in 2022 USD ($)	Sep. 30, 2013 5.25 % Due in 2042 USD ($)	Sep. 30, 2012 5.25 % Due in 2042 USD ($)	Dec. 31, 2011 5.25 % Due in 2042 USD ($)
Debt Instrument [Line Items]
Number of credit facilities retired			2
Amount of credit facility retired			€ 50,000,000	€ 37,000,000	$ 50,000,000						$ 35,000,000	$ 100,000,000
Number of credit facilities			2
Amount of credit facility			50,000,000	37,000,000	50,000,000	100,000,000	70,000,000	75,000,000					35,000,000	100,000,000
Debt retired, amount	43,000,000								300,000,000						100,000,000
Aggregate principal amount of debt										300,000,000						46,000,000	46,000,000	46,000,000	46,000,000	400,000,000	400,000,000	400,000,000	450,000,000	450,000,000	450,000,000	250,000,000	250,000,000	250,000,000
Interest rate on notes									4.875%	4.875%					5.80%	11.50%	2.355%	2.355%	2.355%	2.60%	2.60%	2.60%	3.75%	3.75%	3.75%	5.25%	5.25%	5.25%
Aggregate net proceeds from the issuances		$ 1,100,000,000
Length of credit facility (in years)							5 years	5 years