Long-Term Debt (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended
	Nov. 22, 2011 days	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Maximum [Member]	Dec. 31, 2011 Minimum [Member]	Dec. 31, 2011 2007 Facility [Member]	Nov. 21, 2007 2007 Facility [Member]	Dec. 31, 2011 Term Loan [Member]	Nov. 22, 2011 Swing Line Loan Sub-Facility [Member] Maximum [Member]	Nov. 22, 2011 Letter Of Credit Sub-Facility [Member] Maximum [Member]	Dec. 31, 2011 Federal Funds Effective Rate [Member]	Dec. 31, 2011 LIBOR [Member]	Dec. 31, 2011 Base Rate Loans [Member]	Dec. 31, 2011 Base Rate Loans [Member] Maximum [Member]	Dec. 31, 2011 Base Rate Loans [Member] Minimum [Member]	Feb. 29, 2012 Eurodollar Rate Loans [Member]	Dec. 31, 2011 Eurodollar Rate Loans [Member] Maximum [Member]	Dec. 31, 2011 Eurodollar Rate Loans [Member] Minimum [Member]
Debt Instrument [Line Items]
Revolving credit facility outstanding amount	$ 250,000,000	$ 62,000,000		$ 62,000,000							$ 10,000,000	$ 10,000,000
Increase in revolving credit facility outstanding amount	300,000,000
Term for increase in revolving credit facility before maturity date, days	90
Line of credit facility period (in years)				5
Withdrawal for repayment of existing debt									62,000,000
Line of credit facility, maturity				November 21, 2016
Gain (loss) on early extinguishment of debt		(690,000)	0	(690,000)	0			(690,000)
Interest rate in excess of effective rate													0.50%
Margin over applicable interest rate (basis point)														100	25	25	100	125	125	200
Interest rate at period end										1.563%
Leverage ratio						1.00	2.50
Percentage of capital stock of foreign subsidiaries used as guarantee				65.00%
Capitalized debt issuance costs		1,100,000		1,100,000
Unamortized debt included in other assets		$ 1,100,000		$ 1,100,000