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Stock Compensation - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Sep. 03, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 20.4		$ 20.4
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition				2 years 8 months 12 days
Granted (in shares)				14,164,946
RSUs \| Class B \| Senior management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	760,870
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			900,000
Stock-based compensation expense		0.2		$ 0.9
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition				3 years 2 months 12 days
Stock granted, value, share-based compensation, gross				$ 1.5	$ 2.6
Employee service share-based compensation, nonvested awards, compensation not yet recognized, stock options		$ 2.9		$ 2.9
Stock Option \| Class B \| Senior management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,178,000