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Income Taxes - Narrative (Details) - USD ($) $ in Millions |  | 3 Months Ended | 30 Months Ended |
--- | --- | --- | --- | ---
Jul. 01, 2020 | Jun. 30, 2019 | Jan. 01, 2022 | Dec. 31, 2020
U.S. federal |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Net operating loss carryforwards |  |  |  | $ 2,328
State |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Net operating loss carryforwards |  |  |  | 690
Foreign |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Net operating loss carryforwards |  |  |  | 9
Canadian Tax Authorities | Foreign |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Amount of assessments received, including penalty and interest |  |  |  | 91
Canadian Tax Authorities | Other long-term assets, net | Foreign |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Amount of disputed assessments paid |  |  |  | $ 64
Alberta Government, Canada |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Foreign tax rate | 8.00% | 12.00% |  |
Deferred tax benefit from change in tax rate |  | $ 60 |  |
Alberta Government, Canada | Forecast |  |  |  |
Income Tax Examination [Line Items] |  |  |  |
Foreign tax rate |  |  | 8.00% |

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