Fair Value of Financial Instruments (Details) - USD ($)	3 Months Ended	12 Months Ended
Apr. 03, 2021	Jan. 02, 2021
Money market mutual funds
Fair Value of Financial Instruments
Fair value per share of CRA's money market mutual fund share holdings (in dollars per share)	$ 1.00
Recurring
Fair Value of Financial Instruments
Total Assets	$ 0
Total Liabilities	0
Summary of changes in contingent consideration liability
Beginning balance	14,620,000	$ 11,579,000
Remeasurement of acquisition-related contingent consideration	0	1,156,000
Accretion	380,000	1,885,000
Payment of contingent consideration	(15,000,000)	0
Ending balance	$ 0	14,620,000
Recurring \| Level 1
Fair Value of Financial Instruments
Total Assets		150,000
Contingent consideration liability		0
Total Liabilities		0
Recurring \| Level 1 \| Money market mutual funds
Fair Value of Financial Instruments
Cash and cash equivalents		150,000
Recurring \| Level 2
Fair Value of Financial Instruments
Total Assets		0
Contingent consideration liability		0
Total Liabilities		0
Recurring \| Level 2 \| Money market mutual funds
Fair Value of Financial Instruments
Cash and cash equivalents		0
Recurring \| Level 3
Fair Value of Financial Instruments
Total Assets		0
Contingent consideration liability		14,620,000
Total Liabilities		14,620,000
Recurring \| Level 3 \| Money market mutual funds
Fair Value of Financial Instruments
Cash and cash equivalents		$ 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

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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)
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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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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

Amount of settlements 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)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

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