Stockholders' Equity - Schedule of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Shareholders Equity [Line Items]
Beginning Balance	$ 1,065,466	$ 936,890
Ending Balance	1,101,848	1,002,593
Foreign Currency Translation Gains (Losses)
Shareholders Equity [Line Items]
Beginning Balance	(16,860)	(15,028)
Other comprehensive income (loss)	1,360	2,334
Ending Balance	(15,500)	(12,694)
Unrealized Gains on Investments
Shareholders Equity [Line Items]
Beginning Balance	1,672	339
Other comprehensive income (loss)	1,755	600
Ending Balance	3,427	939
Gains (Losses) on Derivative Instruments
Shareholders Equity [Line Items]
Beginning Balance	3,999
Other comprehensive income (loss)	(461)
Ending Balance	3,538
Accumulated Other Comprehensive Loss
Shareholders Equity [Line Items]
Beginning Balance	(11,189)	(14,689)
Other comprehensive income (loss)	2,654	2,934
Ending Balance	$ (8,535)	$ (11,755)