INCOME TAXES - CURRENT INCOME TAX (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Components of (loss) income before income taxes
Domestic	$ 322,297	$ 134,265	$ 136,239
Foreign	136,142	98,520	386
Income before income taxes	458,439	232,785	136,625
Current:
U.S. federal	26,561	8,240	(7,327)
U.S. state and local	3,575	2,857	(1,266)
Foreign	10,061	22,274	4,208
Total current income taxes	40,197	33,371	(4,385)
Deferred:
U.S. federal	45,079	(128,317)	(13,530)
U.S. state and local	1,317	(9,157)	195
Foreign	(32,613)	3,051	(19,188)
Total deferred income taxes	13,783	(134,423)	(32,523)
Provision for (benefit from) income taxes	$ 53,980	$ (101,052)	$ (36,908)
Reconciliation of effective tax rate to the U.S. statutory federal income tax rate
U.S. federal statutory rate	21.00%	21.00%	31.60%
State and local taxes, net of U.S. federal benefit	2.10%	2.90%	0.50%
Foreign tax rate differential(1)	1.00%	(9.00%)	(6.90%)
Foreign earnings(2)	(9.30%)	5.10%	1.20%
Tax credits(3)	(8.30%)	(15.00%)	(16.50%)
Excess tax benefits from stock-based compensation	(1.80%)	(5.70%)	(38.90%)
One-time transition tax	0.00%	(2.00%)	19.50%
Domestic production deduction	0.00%	0.00%	(2.80%)
Valuation allowance—domestic	0.20%	(46.00%)	(0.50%)
Valuation allowance—foreign(2)	7.30%	0.00%	(2.50%)
Change in reserves	(2.00%)	1.30%	(11.00%)
Other	1.60%	4.00%	(0.70%)
Effective tax rate	11.80%	(43.40%)	(27.00%)
Foreign tax rate differential, amount	$ 19,826