Commitments and Contingencies - Other (Details)	2 Months Ended	6 Months Ended
	Jan. 31, 2011 item	Jun. 30, 2018 USD ($) site item	May 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Commitments And Contingencies [Line Items]
Approximate number of homeowners' properties adjacent to or near certain of our landfills with agreements guaranteeing market value | item		775
Number of landfills adjacent to or near homeowners' properties with agreements guaranteeing market value | item		19
Environmental remediation reasonably possible additional losses high estimate		$ 145,000,000
Environmental remediation liabilities		$ 249,000,000
Number of sites listed on the EPA's NPL for which we have been notified we are a PRP | site		75
Number of owned sites listed on the EPA's NPL for which we have been notified we are a PRP | site		15
Number of non-owned sites listed on the EPA's NPL for which we have been notified we are a PRP | site		60
Dollar threshold for environmental matters requiring disclosure under item 103 of the SEC's Regulation S-K		$ 100,000
Approximate percentage of workforce covered by collective bargaining agreements		20.00%
Expected time of completion of IRS audits		21 months
San Jacinto Waste Pits [Member]
Commitments And Contingencies [Line Items]
Environmental remediation liabilities		$ 55,000,000		$ 55,000,000
Waimanalo Gulch Sanitary Landfill
Commitments And Contingencies [Line Items]
Number of major rainfalls | item	2
Wheelabrator [Member]
Commitments And Contingencies [Line Items]
Maximum future payments		85,000,000
Revolving Credit Facility [Member]
Commitments And Contingencies [Line Items]
Credit Facility, aggregate capacity		$ 2,750,000,000	$ 2,250,000,000