CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 44,862	$ 13,446	$ 185,056	$ 75,323
Other comprehensive (loss) gain:
Foreign currency translation (losses) gains	(1,015)	1,557	(8,468)	10,406
Net unrealized gains (losses) on marketable securities	234	(401)	356	(446)
Other comprehensive (loss) gain	(781)	1,156	(8,112)	9,960
Comprehensive income	$ 44,081	$ 14,602	$ 176,944	$ 85,283

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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