Retirement Plans - Assumptions to Determine Benefit Obligations at Period-end and Net Pension Costs (Detail)	12 Months Ended
	Dec. 31, 2016	Jan. 02, 2016	Dec. 27, 2014
Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit obligation, discount rate	4.25%	4.64%	4.25%
Benefit obligation, annual compensation increase	3.60%	3.60%	3.60%
Net cost, discount rate	4.64%	4.25%	5.19%
Net cost, expected return on plan assets	6.50%	7.00%	7.25%
Net cost, annual compensation increase	3.60%	3.60%	3.60%
Other Postretirement Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit obligation, discount rate	4.25%	4.40%	4.05%
Net cost, discount rate	4.40%	4.05%	4.80%