INCOME TAXES - Reconciliation of Income Tax Expense (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Tax Contingency [Line Items]
Income taxes based on domestic statutory rates	$ 26,943	$ 30,961	$ 88,552
Effect of tax rate differential	(81,213)	(135,033)	(244,128)
Change in unrecognized tax benefit	(896)	(15,381)	22,180
Change in valuation allowance	92,543	191,896	297,330
Recognition of prior year taxes recoverable	13,305	5,439	(53,757)
Expiration of tax attributes	0	4,277	0
APB23 tax liability	8,653	2,047	1,741
Other	11,571	4,521	(19,559)
Provision for income taxes	70,906	88,727	92,359
Income resulting from tax holidays and tax incentives	$ 15,600	$ 24,400	$ 21,700
Effect on basic loss per share due to income resulting from tax holidays and tax incentives (in dollars per share)	$ 0.03	$ 0.05	$ 0.04
Effect on diluted loss per share due to income resulting from tax holidays and tax incentives (in dollars per share)	$ 0.03	$ 0.05	$ 0.04
Tax effect of foreign income not repatriated to Singapore	$ 27,900	$ 7,500	$ 65,800
Valuation Allowance and Deferred Tax Assets, Profitability Forecasted
Income Tax Contingency [Line Items]
Increase (decrease) in valuation allowance	1,100	2,800	1,300
Valuation Allowance and Deferred Tax Assets, Profitability Forecasted \| China
Income Tax Contingency [Line Items]
Increase (decrease) in valuation allowance	3,400
Valuation Allowance and Deferred Tax Assets, Current Period Losses
Income Tax Contingency [Line Items]
Increase (decrease) in valuation allowance	$ 90,200	$ 194,800	$ (65,900)

Effective Income Tax Rate Reconciliation, APB23 Tax Liability, Amount

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