Billed and Unbilled Receivables (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Receivables [Abstract]
Billed receivables	$ 129,079	$ 134,900
Less: allowance for doubtful accounts	(3,887)	(3,860)
Billed receivables, net	125,192	131,041
Unbilled receivables	87,982	80,639
Less: allowance for doubtful accounts	(1,269)	(1,211)
Unbilled receivables, net	$ 86,713	$ 79,428

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

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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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Amount of accumulated credit loss for right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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