Tax Effect of Temporary Differences That Give Rise to Deferred Income Taxes (Detail) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Deferred tax liabilities and (assets):
Property, plant and equipment	$ 581,290	$ 487,026
Inventories	25,989	23,784
Self-insurance reserves	(79,467)	(77,783)
Retirement plan contributions	(41,424)	(42,547)
Postretirement benefit cost	(28,224)	(30,226)
Purchase allowances	(11,114)	(9,967)
Deferred Tax Assets, Investments	(10,811)
Deferred Tax Liabilities, Investments		30,090
Lease accounting	(4,662)	(8,576)
Other	(10,820)	(10,849)
Total deferred tax liabilities	$ 420,757	$ 360,952