CONDENSED CONSOLIDATED STATEMENT OF EQUITY - 9 months ended Dec. 31, 2017 - USD ($) $ in Thousands	Total	Common Stock	Additional paid-in Capital	Retained earnings	Accumulated other comprehensive income	Treasury Stock
Balance, beginning of the period (in shares) at Mar. 31, 2017		132,875,373				(54,582,392)
Balance, beginning of the period at Mar. 31, 2017	$ 738,980	$ 13,288	$ 1,154,429	$ 602,609	$ 7,999	$ (1,039,345)
Increase (Decrease) in Stockholders' Equity
Employee stock awards, benefit plans and other issuances (in shares)		805,768				(389,912)
Employee stock awards, benefit plans and other issuances	5,107	$ 80	15,229			$ (10,202)
Non-cash stock-based compensation (in shares)		487,385
Non-cash stock-based compensation	46,707	$ 49	46,658
Restricted stock units vested (in shares)		1,351,652
Restricted stock units vested		$ 135	(135)
Acquisition of treasury stock (in shares)						(1,588,964)
Acquisition of treasury stock	(39,441)					$ (39,441)
Foreign currency translation	1,827				1,827
Net earnings	18,305			18,305
Balance, end of the period (in shares) at Dec. 31, 2017		135,520,178				(56,561,268)
Balance, end of the period at Dec. 31, 2017	774,111	$ 13,552	1,216,565	623,156	$ 9,826	$ (1,088,988)
Increase (Decrease) in Stockholders' Equity
Cumulative-effect adjustment from adoption of ASU 2016-09	$ 2,626		$ 384	$ 2,242