Accumulated Other Comprehensive Income (Loss) - Summary of Accumulated Other Comprehensive (Loss) (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance				$ 458,907	$ 363,024
Pre-tax Activity		$ 964	$ 738	1,944	1,458
Tax Effect		(238)	(284)	(479)	(562)
Ending Balance		443,222	366,091	443,222	366,091
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		17	(9)	14	(11)
Pre-tax Activity		(12)	22	(8)	26
Tax Effect		3	(8)	2	(10)
Ending Balance		8	5	8	5
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		(93,463)	(92,455)	(94,202)	(92,897)
Ending Balance		(92,737)	(92,001)	(92,737)	(92,001)
Net Pension Activity [Member] | Actuarial Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		(77,915)	(71,897)	(78,618)	(72,393)
Pre-tax Activity		933	807	1,866	1,614
Tax Effect		(230)	(312)	(460)	(623)
Ending Balance		(77,212)	(71,402)	(77,212)	(71,402)
Net Pension Activity [Member] | Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		(39)	(57)	(43)	(61)
Pre-tax Activity		6	7	12	14
Tax Effect		(1)	(2)	(3)	(5)
Ending Balance		(34)	(52)	(34)	(52)
Net Postretirement Benefits Activity [Member] | October 2017 Divestitures [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	[1]	6,220		6,220
Ending Balance	[1]	6,220		6,220
Net Postretirement Benefits Activity [Member] | Actuarial Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		(23,142)	(23,713)	(23,519)	(24,111)
Pre-tax Activity		499	648	998	1,296
Tax Effect		(124)	(250)	(246)	(500)
Ending Balance		(22,767)	(23,315)	(22,767)	(23,315)
Net Postretirement Benefits Activity [Member] | Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		1,396	3,221	1,744	3,679
Pre-tax Activity		(462)	(746)	(924)	(1,492)
Tax Effect		114	288	228	576
Ending Balance		$ 1,048	$ 2,763	$ 1,048	$ 2,763

[1] Recognized loss due to the divestiture of the Deep South and Somerset Exchange Business and the Florence and Laurel Distribution Business during the fourth quarter of 2017.