Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015
Income Tax Disclosure [Line Items]
Alternative Minimum Tax Credit	$ 518
Valuation allowance	1,543
Federal and state research and experimental tax credit	6,293
Liability relating to uncertain tax positions	255
Net after tax expense recognized related to interest	14
Payment of interest accrued	14
Federal
Income Tax Disclosure [Line Items]
Research and development tax credit carryforward	2,620
State
Income Tax Disclosure [Line Items]
Research and development tax credit carryforward	1,767
Valuation allowance related to state tax carryforwards	$ 1,278

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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The amount of estimated interest accrued as of the balance sheet date arising from income tax examinations.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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The current portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

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