Subsequent Events	12 Months Ended
Dec. 30, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On February 29, 2024, CRA announced that its Board of Directors authorized a $35.0 million expansion to its existing share repurchase program. On February 29, 2024, CRA announced that its Board of Directors declared a quarterly cash dividend of $0.42 per common share, payable on March 22, 2024 to shareholders of record as of March 12, 2024.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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