SUMMARY OF ACCOUNTING POLICIES - Other Current Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investment impairments and dispositions	$ 97,691	$ 193,063	$ 21,895
Working capital advances	361,500	271,800
Deferred revenue	361,500	271,800
Working Capital Advances
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Working capital advances	264,200	266,300
Customer-Related Accruals
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Working capital advances	$ 195,100	$ 260,100