Income Taxes - Schedule of Reconciliation of Statutory Federal Income Tax Rate to Effective Income Tax Rate (Detail)	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	(31.00%)	(34.00%)	(34.00%)
Federal rate change	351.00%	(0.00%)	(0.00%)
State income taxes, net of federal benefit	(3.00%)	(0.00%)	1.00%
Deemed dividend and dividends paid	7.00%	20.00%	5.00%
Foreign income tax rate differential	(62.00%)	(1.00%)	5.00%
Stock options	(0.00%)	(0.00%)	1.00%
Research and development tax credit	(1.00%)	(2.00%)	(5.00%)
Deferred warrants	(1.00%)	(2.00%)	0.00%
Reversal of uncertain tax benefits	(3.00%)	(0.00%)	(0.00%)
True-up of NOLs	11.00%	(40.00%)	19.00%
Settlement of intercompany balances	(0.00%)	(0.00%)	(9.00%)
Nondeductible foreign currency exchange remeasurement loss	(0.00%)	(0.00%)	10.00%
Valuation allowance	(268.00%)	63.00%	18.00%
Effective income tax rate	(0.00%)	4.00%	11.00%

Effective Income Tax Rate Reconciliation Deferred Warrants

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Effective Income Tax Rate Reconciliation Nondeductible Foreign Exchange Remeasurement Loss

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Effective Income Tax Rate Reconciliation Reversal Of Uncertain Tax Expense Benefits

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Effective Income Tax Rate Reconciliation True Up Of Net Operating Loss

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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