Inventory - Schedule of Inventory (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 6,316	$ 7,526
Work-in-process	1,327	920
Finished goods	8,633	8,767
Deferred program costs	2,077	2,567
Net inventory	$ 18,353	$ 19,780

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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- Definition

Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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