Revenue - Advertising Revenues (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Disaggregation of Revenue [Line Items]
Advertising revenue	$ 426,895	$ 428,501	$ 1,274,281	$ 1,303,821
Advertising
Disaggregation of Revenue [Line Items]
Advertising revenue	79,253	113,531	253,150	359,380
Digital \| Advertising
Disaggregation of Revenue [Line Items]
Advertising revenue	47,763	54,653	138,452	168,222
Print \| Advertising
Disaggregation of Revenue [Line Items]
Advertising revenue	$ 31,490	$ 58,878	$ 114,698	$ 191,158

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details