CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 444,081	$ 600,801	$ 365,594
Other comprehensive income (loss):
Foreign currency translation adjustments, net of zero tax	17,846	(18,932)	(34,683)
Unrealized gain (loss) on derivative instruments and other, net of zero tax	26,744	(35,417)	(13,992)
Comprehensive income	$ 488,671	$ 546,452	$ 316,919