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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Area of a real estate property.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as current.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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Summary of Significant Accounting Policies - Additional Information (Detail) ft² in Thousands, $ in Millions		1 Months Ended	12 Months Ended
	Apr. 04, 2017	Dec. 31, 2015 USD ($)	Mar. 31, 2017 USD ($) shares	Mar. 31, 2016 USD ($) shares	Mar. 31, 2015 USD ($) shares	Apr. 03, 2017 ft²
Payments received from customers			$ 0.9
Guaranteed annual payments, description			BASF has also agreed to make guaranteed annual payments to the Company through fiscal 2017 and has an option to continue the joint development through fiscal 2018.
Repatriated amount			$ 2.1
Common equivalent shares not included in the calculation of diluted EPS (in shares) \| shares			1,538,418	1,552,959	1,567,352
Net foreign currency transaction and hedging gains (losses)			$ 0.1	$ (2.3)	$ 2.8
Foreign earnings repatriated
Federal and state deferred tax liability			$ 0.7
Tres Amigas
Impairment of minority interest investments				0.7
Blade Dynamics Ltd
Impairment of minority interest investments					$ 3.5
Maximum
Warranty period			3 years
Minimum
Warranty period			1 year
Inox Wind Limited
Strategic agreements value		$ 210.0
Inox Wind Limited \| Maximum
Period allowable to manufacture the electrical control system		4 years
Inox Wind Limited \| Minimum
Period allowable to manufacture the electrical control system		3 years
BASF Corporation
License revenue				$ 3.0
Credit concentration risk \| Accounts receivable \| Inox Wind Limited \| Maximum
Risk percentage			52.00%	84.00%
Credit concentration risk \| Accounts receivable \| Scottish and Southern Energy \| Maximum
Risk percentage			17.00%
Subsequent event
Number of positions eliminated, period percent	8.00%
Subsequent event \| Manufacturing facility
Area of facility (in sq ft) \| ft²						355