Intangibles (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2012	Dec. 31, 2012 Customer relationships	Mar. 31, 2011 Customer relationships	Mar. 31, 2012 Customer relationships	Dec. 31, 2012 Product rights and licenses	Mar. 31, 2011 Product rights and licenses	Mar. 31, 2012 Product rights and licenses	Dec. 31, 2012 Non-compete agreements and other	Mar. 31, 2011 Non-compete agreements and other	Mar. 31, 2012 Non-compete agreements and other	Dec. 31, 2012 Tradename	Mar. 31, 2012 Tradename
Intangible Assets
Weighted-Average Life (in years)						16 years 0 months	16 years 4 months		12 years	12 years		8 years 0 months	13 years
Gross Carrying Amount						$ 520,366		$ 460,054	$ 37,776		$ 37,776	$ 3,727		$ 7,327
Accumulated Amortization	(121,386)		(121,386)		(100,481)	(92,886)		(70,169)	(26,853)		(24,208)	(1,647)		(6,104)
Finite-lived intangible assets, net						427,480		389,885	10,923		13,568	2,080		1,223
Indefinite-lived intangible assets, net															442,644	425,000
Total intangibles, gross	1,004,513		1,004,513		930,157
Total intangibles, net	883,127		883,127		829,676
Amortization expense	$ 8,724	$ 8,497	$ 25,847	$ 25,390