CONVERTIBLE SENIOR NOTES AND CAPPED CALL - Net Impact to Stockholders' Equity (Details) $ in Thousands	12 Months Ended
Mar. 31, 2019 USD ($)
Debt Disclosure [Abstract]
Conversion option	$ 66,700
Payments for capped call transactions	(33,724)
Issuance costs	(1,848)
Total	$ 31,128

Amount of increase (decrease) in additional paid in capital (APIC) resulting from recognition of deferred taxes for convertible debt with a beneficial conversion feature.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 55
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- Definition

Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 25
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- Definition

The amount of subsequent adjustments to additional paid in capital for convertible financial instruments where a component of equity and a component of debt are recognized.

+ References

No definition available.

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- Definition

Amount of increase in additional paid in capital (APIC) resulting from issuance costs from a share-lending arrangement entered into, in contemplation of a convertible debt offering or other financing.

+ References

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