Revenue Recognition - Schedule of Accounts Receivable, Net (Detail) - USD ($)	Dec. 31, 2021	Mar. 31, 2021
Accounts Receivable, after Allowance for Credit Loss, Current [Abstract]
Billed receivables	$ 48,963,000	$ 50,783,000
Allowance for doubtful accounts	(2,668,000)	(3,274,000)
Unbilled receivables	23,250,000	17,213,000
Accounts receivable, net	$ 69,545,000	$ 64,722,000

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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