Accounts Receivable, net - Components of Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 31, 2019
Receivables [Abstract]
Billed receivables	$ 227,787				$ 148,747
Unbilled receivables	360,552				295,103
Less allowance for credit losses	(2,828)				(1,670)
Total accounts receivables, net	$ 585,511	$ 445,429	$ 432,185	$ 420,765	$ 442,180

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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- Definition

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, 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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