INCOME TAXES - Unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 19,600	$ 15,415	$ 12,870
Increases related to prior year tax positions	2,458	325	1,134
Decreases related to prior year tax positions	(1,048)	(292)	(208)
Increases related to current year tax positions	2,433	5,483	3,172
Increases related to current year tax positions	(43)	(1,331)	(1,553)
Balance at end of period	$ 23,400	$ 19,600	$ 15,415

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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