Benefit Plans - Funded Status (Detail) - USD ($) $ in Thousands	Dec. 29, 2019	Dec. 30, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	$ 276,085	$ 255,389
Noncurrent liabilities	114,831	85,682
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(332,304)	(278,957)	$ (303,918)
Plan assets at fair value	276,699	256,168	258,513
Net funded status	(55,605)	(22,789)
Noncurrent liabilities	55,605	22,789
Total liability - postretirement benefits	55,605	22,789
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(62,056)	(64,461)	(76,665)
Plan assets at fair value	0	0	$ 0
Current liabilities	2,831	3,219
Noncurrent liabilities	59,225	61,242
Total liability - postretirement benefits	$ 62,056	$ 64,461