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Principles of Consolidation And Other Matters (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] |  |  |
Operating funds related to regulatory requirements or as collateral under captive insurance arrangements | $ 304,000,000 |  | $ 303,000,000
Equity method investments lag period | 3 months |  |
Gain on investment income, net | $ 26,000,000 | $ 11,000,000 |
Effective tax rate (as a percent) | 23.70% | 24.50% |
Excess tax benefit related to share-based payments, percent | 1.80% | 1.10% |
Unrecognized tax benefits | $ 94,000,000 |  |
Minimum |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] |  |  |
Reasonably possible decrease in unrecognized tax benefits | 0 |  |
Maximum |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] |  |  |
Reasonably possible decrease in unrecognized tax benefits | $ 49,000,000 |  |

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