Income Taxes - Reconciliation of the Financial Statement Recognition and Measurement of Uncertain Tax Positions During the Current Fiscal Year (Detail)	12 Months Ended
Mar. 31, 2019 USD ($)
Income Tax Disclosure [Abstract]
Balance as of March 31, 2018	$ 1,472,000
Additions based on tax positions related to the current year	82,000
Additions for tax positions of prior years	0
Reductions for tax positions related to the current year	0
Reductions for tax positions of prior years	(290,000)
Balance as of March 31, 2019	$ 1,264,000

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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