Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions		Total	Common Stock Class A common stock, Capital Stock	Common Stock Class B common stock, Capital Stock	Treasury Stock Class A common stock, Treasury Stock	Treasury Stock Class B common stock, Treasury Stock	Paid-in Capital	Earnings Invested in the Business		Accumulated Other Comprehensive Income
Balance at beginning of year at Dec. 28, 2014	[1]		$ 36.6	$ 3.5	$ (49.2)	$ (0.6)	$ 24.9	$ 767.4		$ 51.1
Increase (Decrease) in Stockholders' Equity
Issuance of restricted stock and other	[1]				5.5	0.0	0.5
Net earnings	[1]	$ 53.8						53.8
Dividends		(7.7)						(7.7)	[1]
Other comprehensive income (loss), net of tax	[1]	9.6								9.6
Balance at end of year at Jan. 03, 2016	[1]	895.4	36.6	3.5	(43.7)	(0.6)	25.4	813.5		60.7
Increase (Decrease) in Stockholders' Equity
Issuance of restricted stock and other					5.3	0.0	3.2
Net earnings		120.8						120.8
Dividends		(10.7)						(10.7)
Other comprehensive income (loss), net of tax		(2.0)								(2.0)
Balance at end of year at Jan. 01, 2017		1,012.0	36.6	3.5	(38.4)	(0.6)	28.6	923.6		58.7
Increase (Decrease) in Stockholders' Equity
Issuance of restricted stock and other					3.8	0.0	3.6
Net earnings		71.6						71.6
Dividends		(11.6)						(11.6)
Other comprehensive income (loss), net of tax		72.1								72.1
Balance at end of year at Dec. 31, 2017		$ 1,151.5	$ 36.6	$ 3.5	$ (34.6)	$ (0.6)	$ 32.2	$ 983.6		$ 130.8

[1] Fiscal year included 53 weeks.