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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

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- Definition

Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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- Definition

Commitments And Contingencies [Line Items]

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- Definition

Environmental Remediation Reasonably Possible Additional Losses High Estimate

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- Definition

Percentage of entity's employees covered by collective-bargaining arrangement to all participants in multiemployer pension plan.

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- Definition

Number of landfills adjacent to or near homeowners properties with agreements guaranteeing market value.

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- Definition

Number of non-owned sites listed on the environmental protection agency's national priorities list for which we have been notified we are a PRP.

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Number of owned sites listed on environmental protection agency's national priorities list for which we have been notified we are PRP.

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Number of sites listed on the environmental protection agency's national priorities list for which we have been notified we are a PRP.

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Commitments and Contingencies - Other (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) site item	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Commitments And Contingencies [Line Items]
Number of landfills adjacent to or near homeowners' properties with agreements guaranteeing market value \| item	18
Environmental remediation reasonably possible additional losses high estimate	$ 140
Environmental remediation liabilities	$ 230
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
Workforce covered by collective bargaining (as a percent)	20.00%
Withdrawal from Multiemployer Pension Plans [Member]
Commitments And Contingencies [Line Items]
Charge to "Operating" expenses	$ 4	$ 1	$ 3
San Jacinto Waste Pits [Member]
Commitments And Contingencies [Line Items]
Environmental remediation liabilities	$ 55	$ 56