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Fair Value Measurements (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Book Value | Retail |  |
Financial Instruments |  |
Long-term debt | $ 1,500 | $ 1,500
Book Value | Institutional |  |
Financial Instruments |  |
Long-term debt | 536 | 535
Book Value | Other |  |
Financial Instruments |  |
Long-term debt | 1,208 | 746
Fair Value | Level 2 | Retail |  |
Financial Instruments |  |
Long-term debt | 899 | 1,594
Fair Value | Level 2 | Institutional |  |
Financial Instruments |  |
Long-term debt | 395 | 659
Fair Value | Level 2 | Other |  |
Financial Instruments |  |
Long-term debt | $ 1,208 | $ 746
6.7% Senior Notes |  |
Financial Instruments |  |
Interest rate on debt | 6.70% |
Interest rate | Minimum | Institutional and Other |  |
Financial Instruments |  |
Fair value assumption, interest rate | 5.38% | 1.31%
Interest rate | Maximum | Institutional and Other |  |
Financial Instruments |  |
Fair value assumption, interest rate | 8.28% | 4.40%

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