Revenue - Advertising Revenues (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 27, 2021	Jun. 28, 2020	Jun. 27, 2021	Jun. 28, 2020
Disaggregation of Revenue [Line Items]
Advertising revenue	$ 498,497	$ 403,750	$ 971,542	$ 847,386
Advertising
Disaggregation of Revenue [Line Items]
Advertising revenue	112,774	67,760	209,890	173,897
Digital \| Advertising
Disaggregation of Revenue [Line Items]
Advertising revenue	70,995	39,531	130,491	90,689
Print \| Advertising
Disaggregation of Revenue [Line Items]
Advertising revenue	$ 41,779	$ 28,229	$ 79,399	$ 83,208

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