Landfill and Environmental Remediation Liabilities - Summary (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Landfill and environmental remediation liabilities
Total, Environmental Remediation	$ 239
Current (in accrued liabilities)	142	$ 169
Long-term	1,917	1,828
Total	2,059	1,997
Landfill [Member]
Landfill and environmental remediation liabilities
Current (in accrued liabilities), Landfill	114	143
Long-term, Landfill	1,706	1,617
Total, Landfill	1,820	1,760
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Current (in accrued liabilities), Environmental Remediation	28	26
Long-term, Environmental Remediation	211	211
Total, Environmental Remediation	$ 239	$ 237

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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