Related-Party Transactions	12 Months Ended
	Jan. 01, 2022
Related Party Transactions [Abstract]
Related-Party Transactions	Related-Party TransactionsCRA made payments to shareholders of CRA who performed consulting services exclusively for CRA in the amounts of $8.0 million, $9.8 million, and $9.3 million in fiscal 2021, fiscal 2020, and fiscal 2019, respectively. These payments were to exclusive non-employee experts for consulting services performed for CRA's clients in the ordinary course of business.