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Fair Value of Assets and Liabilities - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Segment Reporting Information [Line Items] |  |  |  |
Fair value, asset (liability), unrealized gain (loss), OCI |  |  | $ 0 | $ 0
Corporate |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Fixed asset impairments (current year less than) | $ 1,000,000 | $ 1,000,000 | 1,000,000 | 33,000,000
Corporate | 2019 Business Optimization | Disposition of Acquired Properties |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Asset impairment charges | $ 1,000,000 | $ 0 | $ 1,000,000 | $ 3,000,000

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