Income Taxes - Classification of Deferred Tax (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Net noncurrent deferred tax assets	$ 564	$ 605
Total	$ 564	$ 605

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as noncurrent.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant