Summary of Significant Accounting Policies (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		3 Months Ended			3 Months Ended		3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 North American Business	Dec. 31, 2011 North American Business	Oct. 01, 2011 North American Business Minimum	Mar. 31, 2012 International Business	Dec. 31, 2011 International Business	Mar. 31, 2012 Europe unit	Dec. 31, 2011 Western Europe	Mar. 31, 2012 Western Europe	Mar. 31, 2012 Central Europe	Dec. 31, 2011 Central Europe	Aug. 31, 2011 Central Europe	Mar. 31, 2012 Latin America	Dec. 31, 2011 Latin America	Oct. 01, 2011 Latin America Minimum	Mar. 31, 2012 Australia	Dec. 31, 2011 Australia	Oct. 01, 2011 Australia Minimum	Mar. 31, 2012 UKI	Dec. 31, 2011 UKI	Aug. 31, 2011 UKI
Goodwill
Reporting unit, percentage that fair value exceeded carrying value					40.00%								4.90%			40.00%			40.00%			15.10%
Goodwill impairment charge									$ 46,500
Number of reporting units								3
Gross amount of goodwill
Balance, beginning of period	2,574,285		2,010,241			564,044
Deductible goodwill acquired during the period	4,818		4,818
Currency effects	24,172		5,289			18,883
Balance, end of period	2,603,275		2,020,348			582,927
Accumulated amortization
Balance, beginning of period	320,017		261,362			58,655
Currency effects	637		264			373
Balance, end of period	320,654		261,626			59,028
Net balance	2,282,621	2,254,268	1,758,722	1,748,879		523,899	505,389		46,439	47,891	69,384	63,781		28,461	27,322		62,547	61,697		315,616	306,150
Accumulated Goodwill Impairment Balance	$ 132,409	$ 132,409	$ 85,909	$ 85,909		$ 46,500	$ 46,500