Retirement Plans - Changes in Company's Assets and Related Obligations for its Pension Plans (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Change in projected benefit obligations:
Projected benefit obligations at beginning of the year	$ 392.8	$ 432.9
Service cost pertaining to benefits earned during the year	6.5	9.0	$ 7.2
Interest cost on projected benefit obligations	19.1	18.5	20.3
Actuarial (gains) losses	31.0	(50.1)
Benefits paid to plan participants	(24.7)	(17.5)
Settlements	(7.2)	0.0
Projected benefit obligations at end of the year	417.5	392.8	432.9
Change in fair value of pension assets:
Fair value of pension assets at beginning of the year	280.8	302.1
Actual return on plan assets	19.1	(6.2)
Benefits paid to plan participants	(24.7)	(17.5)
Settlements	(7.2)	0.0
Fair value of pension assets at end of the year	271.9	280.8	$ 302.1
Funded status	(145.6)	(112.0)
Amounts recognized in the consolidated balance sheets:
Non-current assets	1.2	1.6
Current liabilities	(3.7)	(4.0)
Non-current liabilities	(143.1)	(109.6)
Net amount recognized	(145.6)	(112.0)
Amounts recognized in accumulated other comprehensive loss:
Unrecognized net actuarial loss (amounts net of tax: $(30.4) and $(12.7))	(45.3)	(18.2)
Unrecognized prior service cost (amounts net of tax: $0.0 and $(0.1))	0.0	(0.1)
Net amount recognized	(45.3)	(18.3)
Amounts recognized in accumulated other comprehensive loss, net of tax [Abstract]
Unrecognized net actuarial loss amount net of tax	(30.4)	(12.7)
Unrecognized prior service cost amount net of tax	0.0	(0.1)
Funded status of pension plans and SERP (supplemental):
Funded status of qualified defined benefit plans and SERP	(145.6)	(112.0)
Nonqualified trust assets	56.6	64.6
Net funded status of pension plans and SERP (supplemental)	(95.5)	(53.6)
Pension [Member]
Change in fair value of pension assets:
Company contributions	1.5	0.0
SERP [Member]
Change in fair value of pension assets:
Company contributions	2.4	2.4
Funded status of pension plans and SERP (supplemental):
Nonqualified trust assets	$ 50.1	$ 58.4