Receivables and Unbilled Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Components of Receivables [Abstract]
Receivables, net	$ 70,630	$ 60,004
Unbilled receivables, net	46,279	41,255
Receivables and unbilled receivables	116,909	101,259
Allowance for doubtful accounts	396	79
Government contracts receivable	$ 15,200	$ 4,700

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.

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The amount of receivables that are derived from government contracts.

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The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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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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