Fair Value of Financial Instruments (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019
Level 1 \| Recurring
Fair Value of Financial Instruments
Total Assets	$ 150	$ 150
Contingent consideration liability	0	0
Total Liabilities	0	0
Level 2 \| Recurring
Fair Value of Financial Instruments
Total Assets	0	0
Contingent consideration liability	0	0
Total Liabilities	0	0
Level 3 \| Recurring
Fair Value of Financial Instruments
Total Assets	0	0
Contingent consideration liability	14,620	11,579
Total Liabilities	14,620	11,579
Summary of changes in contingent consideration liabilities
Beginning balance	11,579	6,197
Remeasurement of acquisition-related contingent consideration	1,156	3,285
Accretion	1,885	2,097
Ending balance	$ 14,620	11,579
Money market mutual funds
Fair Value of Financial Instruments
Fair value per share of CRA's money market mutual fund share holdings	$ 1.00
Money market mutual funds \| Level 1 \| Recurring
Fair Value of Financial Instruments
Money market mutual funds	$ 150	150
Money market mutual funds \| Level 2 \| Recurring
Fair Value of Financial Instruments
Money market mutual funds	0	0
Money market mutual funds \| Level 3 \| Recurring
Fair Value of Financial Instruments
Money market mutual funds	$ 0	$ 0

Amount of increase in the value of a contingent consideration liability, arising from accretion.

No definition available.

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- Definition

Fair value portion of money market funds per share.

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
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-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

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-Name Accounting Standards Codification
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-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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