Quarterly Financial Information (Unaudited) - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended								12 Months Ended
	May 07, 2023	May 08, 2022	Dec. 30, 2023	Sep. 30, 2023	Jul. 01, 2023	Apr. 01, 2023	Dec. 31, 2022	Oct. 01, 2022	Jul. 02, 2022	Apr. 02, 2022	Dec. 30, 2023	Dec. 31, 2022	Jan. 01, 2022
Quarterly Financial Information [Line Items]
Restructuring charges			$ 23,629	$ 5,975	$ 2,650	$ 22,660	$ 17,352	$ 3,660	$ 18,550	$ 149
Goodwill impairment	$ 0	$ 0									$ 3,586	$ 3,124
Net (loss) income			(88,135)	43,731	50,828	(118,679)	(35,781)	(206,037)	(6,801)	(8,249)	(112,255)	(256,868)	$ 67,125
Provision for (benefit from) income taxes			$ 57,556	$ (38,447)	$ (48,066)	$ 67,580	$ (36,690)	$ (70,748)	$ (701)	$ (1,796)	$ 38,623	$ (109,935)	$ 9,852
Basic (net loss) earnings per share			$ (1.11)	$ 0.55	$ 0.65	$ (1.68)	$ (0.51)	$ (2.93)	$ (0.1)	$ (0.12)	$ (1.46)	$ (3.65)	$ 0.96
Diluted (net loss) earnings per share			$ (1.11)	$ 0.54	$ 0.65	$ (1.68)	$ (0.51)	$ (2.93)	$ (0.1)	$ (0.12)	$ (1.46)	$ (3.65)	$ 0.95
Revenues, net			$ 205,955	$ 214,871	$ 226,830	$ 241,895	$ 222,902	$ 249,718	$ 269,454	$ 297,761	$ 889,551	$ 1,039,835	$ 1,211,165
Gross profit			124,857	141,755	143,180	119,511	125,968	152,351	162,962	180,098	529,303	621,379	726,667
Operating income (loss)			(6,008)	$ 30,607	26,317	(28,583)	(51,778)	(254,529)	13,366	8,970	22,333	(283,971)	196,596
Adjustments
Quarterly Financial Information [Line Items]
Net (loss) income							(3,280)	(1)	(2,178)	(6)		(5,465)	233
Provision for (benefit from) income taxes							$ 2,259	$ 1	$ 2,178	$ 6		$ 4,444	$ 79
Basic (net loss) earnings per share							$ (0.05)	$ 0	$ (0.03)	$ 0		$ (0.08)	$ 0
Diluted (net loss) earnings per share							$ (0.05)	$ 0	$ (0.03)	$ 0		$ (0.08)	$ 0
Revenues, net							$ (1,021)					$ (1,021)	$ (1,298)
Gross profit							(1,021)					(1,021)	312
Operating income (loss)							(1,021)					(1,021)	312
Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Indefinite-lived intangible assets, impairment charges	$ 0
Weekend Health, Inc. d/b/a Sequence
Quarterly Financial Information [Line Items]
Transaction related costs					$ 4,886	$ 3,719					8,605
Kurbo, Inc
Quarterly Financial Information [Line Items]
Goodwill impairment									$ 1,101
Republic of Ireland
Quarterly Financial Information [Line Items]
Goodwill impairment			2,383				2,023
Northern Ireland
Quarterly Financial Information [Line Items]
Goodwill impairment			1,203
Northern Ireland | Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Finite-lived intangible assets, impairment charges			$ 47
United States
Quarterly Financial Information [Line Items]
Revenues, net											$ 604,441	$ 682,428	$ 760,384
United States | Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Indefinite-lived intangible assets, impairment charges							25,739	$ 298,291
Canada | Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Indefinite-lived intangible assets, impairment charges							19,657	13,312	24,485
United Kingdom | Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Indefinite-lived intangible assets, impairment charges							8,275
New Zealand | Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Indefinite-lived intangible assets, impairment charges							0	$ 1,138	$ 834
Australia | Franchise Rights Acquired
Quarterly Financial Information [Line Items]
Indefinite-lived intangible assets, impairment charges							$ 1,872