CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 99,321	$ 71,815	$ 187,826	$ 118,095
Other comprehensive income (loss):
Foreign currency translation adjustment	18,861	(12,567)	23,562	(21,364)
Cash flow hedges:
Change in unrealized gains	0	5,889	(3,817)	6,092
Reclassification to earnings	0	(4,490)	(1,333)	(3,408)
Tax effect on effective cash flow hedges	0	696	845	687
Change in fair value of effective cash flow hedge	0	2,095	(4,305)	3,371
Change in fair value of available for sale securities	(1,554)	(2)	4,295	720
Other comprehensive income (loss)	17,307	(10,474)	23,552	(17,273)
Comprehensive income	$ 116,628	$ 61,341	$ 211,378	$ 100,822