v3.20.2

Income Taxes​ (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) points | Sep. 30, 2019 USD ($) points
Income Tax Disclosure [Abstract] |  |  |  |
Effective income tax rate, including discrete items | 66.70% | (242.90%) | 11.70% | 80.00%
Effective Income Tax Rate Reconciliation, Percentage Points | points |  |  | 9.3 | 59.0
Income Tax Expense (Benefit) |  |  |  |
Provision for depreciation and amortization | $ 2 | $ (5) | $ (5) | $ 45
Impact of change in estimated annual effective tax rate on previous quarter’s pretax income | 51 | 22 | 0 | 0
Interim period treatment of operational losses in foreign jurisdictions for which no tax benefit is recognized* | $ (48) | $ 0 | $ 1 | $ 0
Other discrete items | 5 | 0 | 9 | 1
Provision for income taxes (H) | $ 10 | $ 17 | $ 5 | $ 46

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