Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014	Jul. 27, 2015	Apr. 30, 2013
Net income:
(Loss) Income	$ (25.7)	$ 22.6	$ 5.2	$ 58.0
Shares
Shares	35,000,000	35,300,000	35,000,000	35,300,000
Per Share Amount
NET (LOSS) INCOME (in dollars per share)	$ (0.73)	$ 0.64	$ 0.15	$ 1.64
Effect of dilutive securities
Common stock equivalents (in shares)		100,000	100,000	100,000
Net Income
Net income	$ (25.7)	$ 22.6	$ 5.2	$ 58.0
Weighted average number of shares:
Weighted average number of shares	35,000,000	35,400,000	35,100,000	35,400,000
Per Share Amount
Net income (in dollars per share)	$ (0.73)	$ 0.64	$ 0.15	$ 1.64
Shares repurchased
Options to purchase shares of Class A common stock	300,000	300,000	300,000	300,000
Number of shares of the entity's Class A common stock authorized to be repurchased					$ 100.0	$ 90.0
Number of shares repurchased	234,723	148,970	583,829	495,552
Cost of shares repurchased	$ 12.5	$ 9.1	$ 32.0	$ 29.1
April 30, 2013
Shares repurchased
Number of shares repurchased	145,026	148,970	494,142	495,552
Cost of shares repurchased	$ 7.7	$ 9.1	$ 27.2	$ 29.1
July 27, 2015
Shares repurchased
Number of shares repurchased	89,697		89,697
Cost of shares repurchased	$ 4.8		$ 4.8