Property and Equipment - Depreciation and Amortization Expense Including Amortization Expense for Assets Recorded as Capital Leases (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 1,292	$ 1,333	$ 1,297
Tangible Property and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	834	853	833
Landfill airspace [Member]
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	380	400	395
Property and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 1,214	$ 1,253	$ 1,228