Subsequent Event (Details) (USD $)	1 Months Ended		6 Months Ended		12 Months Ended
	Apr. 30, 2012	Nov. 01, 2011	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2012
Subsequent Event (Details) [Abstract]
Cost of acquired companies, net of cash acquired	$ 520,000,000	$ 257,200,000	$ 257,658,000	$ 0
Acquired Business Estimated Revenue					$ 500,000,000
Acquired Business Operational Statistics			It operates in over 50 countries and has approximately 2,500 employees.