Deferred Revenue - Current and Non-current Balances (Details) - USD ($) $ in Thousands	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Disaggregation of Revenue [Line Items]
Deferred revenue, current	$ 58,899	$ 55,870
Deferred revenue, noncurrent	20,828	21,530
Deferred revenue	79,727	77,400	$ 72,278
Product Protection Plans
Disaggregation of Revenue [Line Items]
Deferred revenue, current	33,810	30,547
Deferred revenue, noncurrent	337	364
Deferred revenue	34,147	30,911	28,775
Eye Care Clubs
Disaggregation of Revenue [Line Items]
Deferred revenue, current	25,089	25,320
Deferred revenue, noncurrent	20,491	21,166
Deferred revenue	45,580	46,486	43,488
HMO Memberships
Disaggregation of Revenue [Line Items]
Deferred revenue, current	0	3
Deferred revenue, noncurrent	0	0
Deferred revenue	$ 0	$ 3	$ 15