Components of Deferred Taxes (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Components of Deferred Tax Provision [Line Items]
Self-insurance reserves	$ 84,915	$ 87,483
Compensation accruals	55,788	49,302
State and foreign net operating loss carryforwards and other state and foreign deferred tax assets	60,521	57,204
Other currently non-deductible accrued liabilities	16,739	24,587
Net pension liability-OCI only	11,746	6,390
Doubtful accounts and other reserves	18,428	33,905
Other combined items-OCI only	2,615us-gaap_DeferredTaxAssetsOther	9,018us-gaap_DeferredTaxAssetsOther
Deferred income tax assets, Gross	250,752us-gaap_DeferredTaxAssetsGross	267,889us-gaap_DeferredTaxAssetsGross
Less: Valuation Allowance	(52,764)	(46,841)
Net deferred income tax assets:	197,988us-gaap_DeferredTaxAssetsNet	221,048us-gaap_DeferredTaxAssetsNet
Depreciable and amortizable assets	(362,674)	(337,669)
Other deferred tax liabilities	(2,963)us-gaap_DeferredTaxLiabilitiesOther	(2,624)us-gaap_DeferredTaxLiabilitiesOther
Net deferred income tax liabilities	$ (167,649)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (119,245)us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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