Income Taxes - Summary of Consolidated Effective Tax Rates (Detail)	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Income Tax Disclosure [Abstract]
Statutory federal rate	35.00%	35.00%	35.00%
State income taxes after federal income tax	0.40%	5.00%	9.30%
Valuation allowance	5.70%	(2.30%)	2.60%
Accounting for Stock Options	2.10%	1.90%	2.70%
Research & Development credit	(43.50%)
Uncertain tax position expense	1.90%
Other	(4.60%)	(2.60%)	(1.40%)
Consolidated effective tax rate	(3.00%)	37.00%	48.20%

Effective income tax rate reconciliation nondeductible expense uncertainty in income tax positions.

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage 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 changes in the valuation allowance for deferred tax assets.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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