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Income Taxes (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Income Tax Disclosure [Abstract] |  |  |
Undistributed earnings of foreign subsidiaries | $ 700,000,000 |  |
Effective tax rate | 26.70% | 27.30% | 25.60%
Net increases in valuation allowances | $ 72,000,000 | $ 60,000,000 | $ 36,000,000
Decreased income tax expense due to adjustments to valuation allowance | $ (14,000,000) | 0 | 1,000,000
Net operating loss carryforwards (as a percent) | 58.00% |  |
Tax Credit Carryforward [Line Items] |  |  |
Differences related to non-U.S. operations | $ 569,000,000 | 400,000,000 |
Unrecognized tax benefits | 90,000,000 | 75,000,000 | 64,000,000
Accrued interest and penalties, before any applicable federal benefit | 40,000,000 | $ 31,000,000 | $ 15,000,000
Minimum |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Reasonably possible decrease in unrecognized tax benefits | 0 |  |
Maximum |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Reasonably possible decrease in unrecognized tax benefits | 33,000,000 |  |
Federal |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Operating loss carryforwards tax benefits | 24,000,000 |  |
State and Local |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Differences related to non-U.S. operations | 60,000,000 |  |
Operating loss carryforwards tax benefits | 25,000,000 |  |
Non-U.S. |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Operating loss carryforwards tax benefits | $ 94,000,000 |  |

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