Stockholders' Equity (Changes in Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance at March 31, 2014			$ 529,000
Other comprehensive income (loss) before reclassifications			(2,816,000)
Amounts reclassified from AOCI			259,000	[1]
Tax effect of other comprehensive income items	(48,000)	(48,000)	(96,000)		(96,000)
Other comprehensive income (loss), net of tax	(5,310,000)	2,109,000	(2,653,000)		(374,000)
Balance at September 30, 2014	(2,124,000)		(2,124,000)
Senior notes, net [Member] | 3.25% senior notes due October 2015 [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Debt instrument, face amount	250,000,000		250,000,000
Debt instrument, interest rate	3.25%		3.25%
Accumulated Translation Adjustment [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance at March 31, 2014			1,018,000
Other comprehensive income (loss) before reclassifications			(2,816,000)
Amounts reclassified from AOCI			0
Tax effect of other comprehensive income items			0
Other comprehensive income (loss), net of tax			(2,816,000)
Balance at September 30, 2014	(1,798,000)		(1,798,000)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance at March 31, 2014			(489,000)
Other comprehensive income (loss) before reclassifications			0
Amounts reclassified from AOCI			259,000	[1]
Tax effect of other comprehensive income items			(96,000)
Other comprehensive income (loss), net of tax			163,000
Balance at September 30, 2014	$ (326,000)		$ (326,000)

[1] The reclassifications out of AOCI were associated with a loss on a treasury rate lock agreement from July 2010 related to the issuance of the Company’s $250 million of 3.25% senior notes maturing on October 1, 2015 (the “2015 Notes”), which is being reclassified into earnings (interest expense) over the term of the 2015 Notes. The effects on the respective line items of the consolidated statements of earnings impacted by the reclassifications were not material for the six months ended September 30, 2014 and 2013.