Subsequent Events	12 Months Ended
Jan. 02, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On February 4, 2021, CRA's Board of Directors authorized the repurchase of an additional $40.0 million of shares of CRA's common stock under its existing share repurchase program. On March 4, 2021, CRA announced that its Board of Directors declared a quarterly cash dividend of $0.26 per common share, payable on March 26, 2021 to shareholders of record as of March 16, 2021.

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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