Revenue - Subscription, Advertising, and Other Revenues (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 29, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 27, 2020	Dec. 29, 2019	Dec. 30, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 509,358	$ 426,895	$ 403,750	$ 443,636	$ 508,363	$ 428,501	$ 436,258	$ 439,062	$ 1,783,639	$ 1,812,184	$ 1,748,598
Subscription
Disaggregation of Revenue [Line Items]
Revenues									1,195,368	1,083,851	1,042,571
Advertising
Disaggregation of Revenue [Line Items]
Revenues									392,420	530,678	558,253
Other
Disaggregation of Revenue [Line Items]
Revenues									195,851	197,655	147,774
Real Estate
Disaggregation of Revenue [Line Items]
Revenue not from contract with customer									$ 29,000	$ 31,000	$ 23,000