v3.22.0.1

Income Taxes - Expiration Periods of Deferred Tax Asset​s (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Deferred Tax Asset Expiration [Line Items] |  |  |  |
Tax loss carryforwards | $ 206 | $ 167 |  |
Employee benefits | 331 | 503 |  |
Other | 175 |  |  |
Valuation allowance | (90) | (91) | $ (113) | $ (107)
Deferred tax assets, net | 622 | $ 694 |  |
Expires within 10 years |  |  |  |
Deferred Tax Asset Expiration [Line Items] |  |  |  |
Tax loss carryforwards | 34 |  |  |
Employee benefits | 0 |  |  |
Other | 0 |  |  |
Valuation allowance | (32) |  |  |
Deferred tax assets, net | 2 |  |  |
Expires within 11-20 years |  |  |  |
Deferred Tax Asset Expiration [Line Items] |  |  |  |
Tax loss carryforwards | 30 |  |  |
Employee benefits | 0 |  |  |
Other | 2 |  |  |
Valuation allowance | (6) |  |  |
Deferred tax assets, net | 26 |  |  |
No Expiration |  |  |  |
Deferred Tax Asset Expiration [Line Items] |  |  |  |
Tax loss carryforwards | 142 |  |  |
Employee benefits | 0 |  |  |
Other | 44 |  |  |
Valuation allowance | (5) |  |  |
Deferred tax assets, net | 181 |  |  |
Other |  |  |  |
Deferred Tax Asset Expiration [Line Items] |  |  |  |
Tax loss carryforwards | 0 |  |  |
Employee benefits | 331 |  |  |
Other | 129 |  |  |
Valuation allowance | (47) |  |  |
Deferred tax assets, net | $ 413 |  |  |

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