Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 44,588	$ 88,923
Other comprehensive income (loss):
Foreign currency translation gain	1,360	2,334
Unrealized loss on derivative instrument	(461)
Net unrealized gains on marketable securities	1,755	600
Other comprehensive income	2,654	2,934
Comprehensive income	$ 47,242	$ 91,857