Postretirement Plans - Additional Information (Detail) - USD ($)	3 Months Ended			4 Months Ended	12 Months Ended
	Dec. 31, 2016	Oct. 08, 2016	Jul. 16, 2016	Apr. 23, 2016	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015	Dec. 31, 2015
Pension and Other Postretirement Benefits Disclosure [Line Items]
Settlement loss	$ (173,000)	$ (1,832,000)	$ (4,641,000)	$ 0	$ (6,646,000)		$ (15,387,000)
Expected pension income for fiscal 2017					$ 5,000,000
Expected long-term rate of return on plan assets					8.00%
Percentage of total plan assets	100.00%				100.00%	100.00%
Expected company contribution					$ 692,000
Postretirement Benefits, minimum years of service for eligibility					10 years
Postretirement Benefits, minimum age for eligibility					55 years
Expense under plans					$ 2,238,000	$ (5,878,000)	$ 5,341,000
Multiemployer plans, minimum contribution	$ 0				$ 0
Minimum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Retiree medical coverage provided					3 years
Maximum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Retiree medical coverage provided					5 years
Contribution of pension fund in excess of total contribution					5.00%	5.00%	5.00%
Common Stock
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined benefit plan equity securities included in common stock	2,030,363				2,030,363			2,030,363
Equity securities, amount	$ 40,500,000				$ 40,500,000			$ 43,600,000
Percentage of total plan assets	12.10%				12.10%			11.80%
Equity Securities
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted equities					65.00%
Percentage of total plan assets	51.10%				51.10%	55.60%
Pension plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Settlement loss					$ (6,646,000)		$ (15,387,000)
Actual return on plan assets					4,689,000	$ 6,881,000	$ 11,600,000
Amortization from accumulated other comprehensive income into net periodic cost (benefit)					$ 6,800,000
Expected long-term rate of return on plan assets					8.00%	8.00%	8.00%
Contribution of company to company pension plans					$ 1,341,000	$ 10,436,000	$ 13,435,000
Pension plans | Required
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contribution of company to company pension plans					341,000	436,000	5,070,000
Pension plans | Discretionary
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contribution of company to company pension plans					$ 1,000,000	10,000,000	8,365,000
Last Fifteen Years
Pension and Other Postretirement Benefits Disclosure [Line Items]
Average annual return on the plan assets					6.90%
Inception in 1987
Pension and Other Postretirement Benefits Disclosure [Line Items]
Average annual return on the plan assets					8.90%
Last Five Years
Pension and Other Postretirement Benefits Disclosure [Line Items]
Average annual return on the plan assets					8.50%
Non Qualified Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected company contribution					$ 300,000
Non Qualified Pension Plans | Required
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contribution of company to company pension plans						300,000
Qualified Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected company contribution					0
Qualified Pension Plans | Discretionary
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contribution of company to company pension plans						1,000,000
Postretirement Benefit Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Amortization from accumulated other comprehensive income into net periodic cost (benefit)					(700,000)
Contribution of company to company pension plans					841,000	674,000
Expected company contribution					692,000
Contributions by participants					284,000	224,000	200,000
Multiemployer Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expense under plans					$ 2,200,000	$ 2,100,000	$ 2,100,000
Red Zone
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of funded under multi employer plans					Less than 65 percent
Yellow Zone
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of funded under multi employer plans					Between 65 and less than 80 percent
Green Zone
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of funded under multi employer plans					At least 80 percent