Earnings per Share and Stock Repurchase Program (Details) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2021 USD ($) $ / shares shares	Jun. 28, 2020 USD ($) $ / shares shares	Jun. 27, 2021 USD ($) $ / shares shares	Jun. 28, 2020 USD ($) $ / shares shares	Dec. 31, 2020	Feb. 06, 2019 USD ($)
Net (loss) income
Net income	$ 37.5	$ 20.2	$ 79.2	$ 52.2
Shares
Shares (in shares) | shares	33,800,000	33,800,000	33,800,000	33,900,000
Per Share Amount
Net income (in dollars per share) | $ / shares	$ 1.11	$ 0.60	$ 2.34	$ 1.54
Dilutive securities, principally common stock options
Common stock equivalents (in shares) | shares	100,000	200,000	100,000	100,000
Common stock equivalents (in dollars per share) | $ / shares		$ (0.01)		$ (0.01)
Net (loss) income
Net income	$ 37.5	$ 20.2	$ 79.2	$ 52.2
Weighted average number of shares:
Shares (in shares) | shares	33,900,000	34,000,000.0	33,900,000	34,000,000.0
Securities not included in the computation of diluted EPS
Net income (in dollars per share) | $ / shares	$ 1.11	$ 0.59	$ 2.34	$ 1.53
Dilutive securities, principally common stock options
Options to purchase shares of Class A common stock, anti-dilutive | shares	0	0	0	0
Shares repurchased
Number of shares repurchased | shares	30,917	78,828	62,070	253,535
Stock Repurchased During Period, Value	$ 4.0	$ 6.4	$ 7.8	$ 21.1
Cost of shares repurchased			$ 7.8	$ 21.1
Class A
Common Stock
Common Stock, votes per share (Number of votes)	1		1		1
Class B
Common Stock
Common Stock, votes per share (Number of votes)	10		10		10
February 6, 2019 | Class A
Shares repurchased
Value of shares of the entity's Class A common stock authorized to be repurchased						$ 150.0
Remaining authorized repurchase amount	$ 105.6		$ 105.6