Fair Value of Assets and Liabilities - Narrative (Details) - Corporate - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Fixed asset impairments	$ 1,000,000	$ 0	$ 33,000,000	$ 1,000,000
Asset impairment charges			33,000,000
Disposition of Acquired Properties \| 2019 Business Optimization
Segment Reporting Information [Line Items]
Asset impairment charges	$ 0	$ 0	$ 3,000,000	$ 0

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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-SubTopic 10
-Section 45
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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