Components of Deferred Taxes (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Self-insurance reserves	$ 85,940	$ 88,401
Compensation accruals	83,328	66,399
Doubtful accounts and other reserves	38,017	29,616
Other currently non-deductible accrued liabilities	24,058	17,213
State and foreign net operating loss carryforwards and other state and foreign deferred tax assets	66,639	62,541
Net pension liabilities – OCI only	5,926	10,929
Other combined items – OCI only	815	457
Deferred income tax assets, Gross	304,723	275,556
Valuation Allowance	(56,333)	(52,567)
Total deferred income taxes	248,390	222,989
Depreciable and amortizable assets	332,326	400,809
Other liabilities	2,949	2,960
Deferred income tax liabilities, Gross	$ 335,275	$ 403,769