Retirement Plans - Changes in Company's Assets and Related Obligations for its Pension Plans (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Change in projected benefit obligations:
Projected benefit obligations at beginning of the year	$ 443.4	$ 417.5
Interest cost on projected benefit obligations	16.5	17.7	$ 19.1
Actuarial loss (gain)	(31.6)	30.5
Benefits paid to plan participants	(19.2)	(27.2)
Curtailment	0.0	(2.3)
Service cost pertaining to benefits earned during the year	6.3	7.2	6.5
Settlement	(66.6)	0.0
Projected benefit obligations at end of the year	348.8	443.4	417.5
Change in fair value of pension assets:
Fair value of pension assets at beginning of the year	299.6	271.9
Actual return (loss) on plan assets	(22.6)	41.0
Benefits paid to plan participants	(19.2)	(27.2)
Settlement	(66.6)	0.0
Fair value of pension assets at end of the year	254.4	299.6	271.9
Funded status	(94.4)	(143.8)
Amounts recognized in the consolidated balance sheets:
Non-current assets	1.4	2.1
Current liabilities	(3.8)	(3.7)
Non-current liabilities	(92.0)	(142.2)
Net amount recognized	(94.4)	(143.8)
Funded status of pension plans and SERP (supplemental):
Funded status of qualified defined benefit plans and SERP	(94.4)	(143.8)
Nonqualified trust assets	64.4	60.7
Net funded status of pension plans and SERP (supplemental)	(37.0)	(89.8)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(7.2)	0.0	$ 0.1
Pension [Member]
Change in fair value of pension assets:
Company contributions	60.7	11.3
SERP [Member]
Change in fair value of pension assets:
Company contributions	2.5	2.6
Funded status of pension plans and SERP (supplemental):
Nonqualified trust assets	$ 57.4	$ 54.0