Revenue - Schedule of Revenues Disaggregated by Revenue Source (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2024	Apr. 01, 2023
Disaggregation Of Revenue [Line Items]
Revenues, net	$ 206,548	$ 241,895
Digital Subscription Revenues
Disaggregation Of Revenue [Line Items]
Revenues, net	137,633	149,344
Workshops + Digital Subscription Revenues
Disaggregation Of Revenue [Line Items]
Revenues, net	47,671	61,688
Clinical Subscription Revenues
Disaggregation Of Revenue [Line Items]
Revenues, net	18,752
Subscription Revenues, net
Disaggregation Of Revenue [Line Items]
Revenues, net	204,056	211,032
Other Revenues, net
Disaggregation Of Revenue [Line Items]
Revenues, net	$ 2,492	$ 30,863