Consolidated Statements of Stockholders' Equity (Unaudited) (USD $) In Millions	Additional Paid-in Capital [Member]	Earnings Invested In The Business [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Common Class A [Member]	Common Class B [Member]	Common Class A Treasury Stock [Member]	Common Class B Treasury Stock [Member]	Total
Balance at Jan. 01, 2012	$ 28.8	$ 657.5	$ 16.2	$ 36.6	$ 3.5	$ (66.3)	$ (0.6)
Other comprehensive income, net of tax			8.3					8.3
Net earnings		9.6						9.6
Dividends		(1.9)
Exercise of stock options, restricted stock and other	1.0
Exercise of stock options, restricted stock awards and other						0.3
Balance at Apr. 01, 2012	29.8	665.2	24.5	36.6	3.5	(66.0)	(0.6)	693.0
Balance at Dec. 30, 2012	27.1	700.0	35.4	36.6	3.5	(61.0)	(0.6)	741.0
Other comprehensive income, net of tax			5.3					5.3
Net earnings		12.9						12.9
Dividends		(1.9)
Exercise of stock options, restricted stock and other	0.7
Exercise of stock options, restricted stock awards and other						0.5
Balance at Mar. 31, 2013	$ 27.8	$ 711.0	$ 40.7	$ 36.6	$ 3.5	$ (60.5)	$ (0.6)	$ 758.5