Billed and Unbilled Receivables (Details) - USD ($) $ in Thousands	Sep. 28, 2019	Dec. 29, 2018
Receivables [Abstract]
Billed receivables	$ 114,148	$ 101,482
Less: allowance for doubtful accounts	(4,557)	(3,158)
Billed receivables, net	109,590	98,324
Unbilled receivables	55,206	44,799
Less: allowance for doubtful accounts	(1,388)	(1,388)
Unbilled receivables, net	$ 53,818	$ 43,411

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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