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v3.21.2

Fair Value Measurements (Details) - USD ($) $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
6.7% Senior Notes |  |
Financial Instruments |  |
Interest rate | 6.70% |
Book Value | Retail |  |
Financial Instruments |  |
Long-term debt | $ 1,842 | $ 1,917
Book Value | Institutional |  |
Financial Instruments |  |
Long-term debt | 535 | 535
Book Value | Other |  |
Financial Instruments |  |
Long-term debt | 397 | 106
Fair Value | Level 2 | Retail |  |
Financial Instruments |  |
Long-term debt | 1,942 | 1,962
Fair Value | Level 2 | Institutional |  |
Financial Instruments |  |
Long-term debt | 670 | 707
Fair Value | Level 2 | Other |  |
Financial Instruments |  |
Long-term debt | $ 397 | $ 106
Interest rate | Institutional and Other | Minimum |  |
Financial Instruments |  |
Fair value assumption, interest rate | 1.26% | 1.35%
Interest rate | Institutional and Other | Maximum |  |
Financial Instruments |  |
Fair value assumption, interest rate | 4.34% | 3.75%

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