Significant Clients - Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 27, 2020 USD ($) Client	Mar. 29, 2019 USD ($) Client	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Revenue, percent	100.00%
Accounts receivable, net	$ 71,162		$ 88,772
Number of major client \| Client	1	1
Number of other major client \| Client	0	0
Customer Concentration Risk [Member] \| Sales Revenue, Services, Net [Member]
Segment Reporting Information [Line Items]
Revenue, percent	100.00%	100.00%
IBM [Member]
Segment Reporting Information [Line Items]
Revenue	$ 19,900	$ 20,900
Extended period of services agreement	6 months
Services agreement expiration date	Jul. 03, 2020
Accounts receivable, net	$ 10,000		$ 23,000
IBM [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Services, Net [Member]
Segment Reporting Information [Line Items]
Revenue, percent	22.90%	21.60%

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Number of other major client.

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Services agreement expiration date.

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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