SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Trade Receivables, Net (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Supplemental Balance Sheet Information [Abstract]
Client receivables	$ 395,740	$ 370,131
Unbilled revenue	121,957	105,216
Total	517,697	475,347
Less: Allowance for doubtful accounts	(3,664)	(3,099)
Trade receivables, net	$ 514,033	$ 472,248

-- None. No documentation exists for this element. --

No definition available.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for billed goods or services.

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Amount, before 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, 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, before 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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