SHORT-TERM INVESTMENTS (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	$ 556,337	$ 743,892
Gross Unrealized Gain	1,344	769
Gross Unrealized Losses	(28)	(176)
Fair Value	557,653	744,485
Bank-time deposits
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	254,417	387,720
Gross Unrealized Gain	0	0
Gross Unrealized Losses	0	0
Fair Value	254,417	387,720
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	259,496	295,526
Gross Unrealized Gain	1,280	742
Gross Unrealized Losses	(25)	(127)
Fair Value	260,751	296,141
US Treasuries
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	35,388	55,656
Gross Unrealized Gain	64	27
Gross Unrealized Losses	(3)	(49)
Fair Value	35,449	55,634
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cost or Amortized Cost	7,036	4,990
Gross Unrealized Gain	0
Gross Unrealized Losses	0
Fair Value	$ 7,036	$ 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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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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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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