Credit Facilities and Long-Term Debt (Details Textual) In Millions, unless otherwise specified		6 Months Ended		6 Months Ended		0 Months Ended
	Oct. 31, 2011 Letter of Credit USD ($)	Jun. 30, 2013 Revolving Credit Facility	Oct. 31, 2011 Revolving Credit Facility USD ($)	Jun. 30, 2013 Risk Sharing Finance Facility Agreement [Member] USD ($)	Dec. 14, 2012 Risk Sharing Finance Facility Agreement [Member] EUR (€)	Sep. 20, 2011 Senior Notes	Jun. 30, 2013 Senior Notes Due 2016, 3.550% USD ($)	Dec. 31, 2012 Senior Notes Due 2016, 3.550% USD ($)	Sep. 20, 2011 Senior Notes Due 2016, 3.550%	Jun. 30, 2013 Senior Notes Due 2021, 4.875% USD ($)	Dec. 31, 2012 Senior Notes Due 2021, 4.875% USD ($)	Sep. 20, 2011 Senior Notes Due 2021, 4.875%
Credit Facilities and Long-Term Debt [Abstract]
Interest on notes due									3.55%			4.875%
Fair value of senior notes due							$ 632	$ 639		$ 636	$ 680
Interest payment failure period						30 days
Other covenant default period after servicing of notice						90 days
Percentage of holding required for servicing of notice						25.00%
Redemption price percentage						101.00%
Debt instrument aggregate principal amount	$ 100		$ 600	$ 157	€ 120
Interest rate per annum, effective rate		1.00%
Maximum leverage ratio		3.50		3.50