Income Taxes - Summary of Provision for (Benefit of) Income Taxes Differs from the Amount Computed at Federal Statutory Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Tax expense at United States federal statutory rate	$ 1,948	$ 895	$ 6,150
Research and development tax credits	(3,449)	(4,705)	(4,647)
Impact of foreign operations	(1,203)	(683)	(304)
Impact of deferred adjustments	(251)	159	132
Impact of audit settlements	(56)	(61)	967
Return to provision true-ups	(15)	(1,868)	(149)
Impact of amended returns	(9)	67	391
Acquisition expenses		229	(2)
Foreign transition tax - Tax Reform			210
Revaluation of deferred tax balances - Tax Reform			231
Impact of uncertain tax positions	278	1,062	375
Non-deductible expenses	517	903	140
Impact of valuation allowance	563	(49)	(33)
State income taxes	572	687	1,502
Compensation	865	125	(169)
Provision for (benefit of) income taxes	$ (240)	$ (3,239)	$ 4,794

Income tax reconciliation acquisition expenses (benefit).

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Income tax reconciliation impact of amended returns.

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Income tax reconciliation impact of deferred adjustments.

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Income tax reconciliation impact of foreign operations.

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Income tax reconciliation impact of uncertain tax positions.

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Income tax reconciliation nondeductible expense (benefit).

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Income tax reconciliation return to provision true-ups.

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Income tax reconciliation revaluation of deferred tax balances tax reform.

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

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Amount 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 increase (decrease) in the valuation allowance for deferred tax assets.

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Amount 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 increase (decrease) in the income tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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