Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Apr. 02, 2021	Jan. 01, 2021
Statement Of Financial Position [Abstract]
Accounts receivable and unbilled revenue, allowance	$ 647	$ 605
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	1,250,000	1,250,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	57,987,246	57,600,158
Treasury stock, at cost, shares	27,744,777	27,609,752

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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