Stock Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 02, 2020	Mar. 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company recognized total stock compensation expense, net of forfeitures	$ 9.8	$ 7.7
LTIA AND Prior Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company recognized total stock compensation expense, net of forfeitures	$ 9.8	$ 7.7
Class A [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	443,775
Grant date value of shares vested	$ 29.7
Class A [Member] \| Board of Directors Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	38,249
Fair Value Of Shares Granted	$ 2.5
Class A [Member] \| Market Based LTIA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	197,258
Fair Value Of Shares Granted	$ 6.2
Class A [Member] \| Service Based LTIA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	324,756
Fair Value Of Shares Granted	$ 16.6
Class A [Member] \| Performance Based LTIA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	175,815
Fair Value Of Shares Granted	$ 9.2

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