| Income Taxes - Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2018 | 
|---|---|---|---|
| Deferred income tax assets | |||
| Net operating loss carryforward | $ 21,913 | $ 23,471 | $ 25,848 | 
| Stock-based compensation | 3,775 | 3,996 | 3,095 | 
| Other | 2,312 | 1,228 | 2,732 | 
| Gross deferred income tax assets | 28,000 | 28,695 | 31,675 | 
| Valuation allowance | (15,710) | (27,972) | (30,394) | 
| Net deferred income tax assets | 12,290 | 723 | 1,281 | 
| Deferred income tax liabilities | |||
| Depreciation and amortization | (1,648) | (678) | (680) | 
| Intangibles and goodwill | (10,356) | 0 | 0 | 
| Other | 0 | (5) | (5) | 
| Net deferred income tax assets / (liabilities) | $ 286 | $ 40 | $ 596 | 
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- Definition Deferred tax liabilities depreciation and amortization. No definition available. 
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- References No definition available. 
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from intangible assets including goodwill. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- References No definition available. 
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- Definition Amount of deferred tax liability attributable to taxable temporary differences classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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