Earnings per Share (Details) (USD $) In Millions, except Per Share data	3 Months Ended		6 Months Ended
	Jul. 03, 2011	Jul. 04, 2010	Jul. 03, 2011	Jul. 04, 2010
Income (loss) (Numerator)
Net income from continuing operations	$ 12.9	$ 22.2	$ 24.0	$ 34.4
Income (loss) from discontinued operations, net of taxes	1.7	(0.1)	1.7	(4.2)
NET INCOME	14.6	22.1	25.7	30.2
Shares (Denominator)
Weighted average number of shares (in shares)	37.6	37.2	37.6	37.2
Basic Per Share Amount
Continuing operations (in dollars per share)	$ 0.34	$ 0.60	$ 0.64	$ 0.93
Discontinued operations (in dollars per share)	$ 0.05		$ 0.05	$ (0.11)
NET INCOME (in dollars per share)	$ 0.39	$ 0.59	$ 0.69	$ 0.82
Effect of dilutive securities
Common stock equivalents (in shares)	0.2	0.2	0.1	0.1
Income (loss) (Numerator)
Continuing operations	12.9	22.2	24.0	34.4
Discontinued operations	1.7	(0.1)	1.7	(4.2)
NET INCOME	$ 14.6	$ 22.1	$ 25.7	$ 30.2
Shares (Denominator)
Weighted average number of shares (in shares)	37.8	37.4	37.7	37.3
Diluted Per Share Amount
Continuing operations (in dollars per share)	$ 0.34	$ 0.59	$ 0.64	$ 0.92
Discontinued operations (in dollars per share)	$ 0.05		$ 0.05	$ (0.11)
NET INCOME (in dollars per share)	$ 0.39	$ 0.59	$ 0.68	$ 0.81
Securities not included in the computation of diluted EPS
Options to purchase shares of Class A Common Stock (in shares)	0.3	0.6	0.3	0.7