SHORT-TERM INVESTMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 698,224	$ 743,892
Gross Unrealized Gain	1,055	769
Gross Unrealized Losses	(10)	(176)
Fair Value	699,269	744,485
Bank-time deposits
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	273,000	387,720
Gross Unrealized Gain	0	0
Gross Unrealized Losses	0	0
Fair Value	273,000	387,720
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	302,418	295,526
Gross Unrealized Gain	1,049	742
Gross Unrealized Losses	(7)	(127)
Fair Value	303,460	296,141
US Treasuries
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	16,030	55,656
Gross Unrealized Gain	6	27
Gross Unrealized Losses	(3)	(49)
Fair Value	16,033	55,634
US Agencies
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	3,499
Gross Unrealized Gain	0
Gross Unrealized Losses	0
Fair Value	3,499
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	103,277	4,990
Gross Unrealized Gain	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 103,277	$ 4,990

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-SubTopic 10
-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Paragraph 1
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