Income Taxes - Components of Net Deferred Tax Assets (Liabilities) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Net operating loss, capital loss and tax credit carry-forwards	$ 297	$ 164
Miscellaneous and other reserves, net	380	356
Subtotal	677us-gaap_DeferredTaxAssetsGross	520us-gaap_DeferredTaxAssetsGross
Valuation allowance	(300)	(149)
Deferred tax liabilities:
Landfill and environmental remediation liabilities	(22)	(30)
Property and equipment	(598)	(966)
Goodwill and other intangibles	(1,095)	(1,104)
Net deferred tax liabilities	$ (1,338)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (1,729)us-gaap_DeferredTaxAssetsLiabilitiesNet

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

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