Significant Accounting and Reporting Policies - Reclassifications Due to Covid-19 (Details) - USD ($) $ in Thousands	Mar. 29, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019
Unusual or Infrequent Item, or Both [Line Items]
Receivables	$ 25,652		$ 63,106	$ 44,331
Inventories	7,394		32,902	42,629
Prepaid advertising and other current assets	33,618		15,921	38,313
Deferred revenue	30,381	$ 151,400	$ 151,377	$ 151,336
Pandemic COVID-19 [Member] | Other Assets [Member]
Unusual or Infrequent Item, or Both [Line Items]
Inventories	39,364
Prepaid advertising and other current assets	5,177
Other current assets, excluding cash and cash equivalents	68,509
Pandemic COVID-19 [Member] | Non-Current Deferred Revenue [Member]
Unusual or Infrequent Item, or Both [Line Items]
Receivables	23,968
Deferred revenue	$ 154,946