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v3.19.3.a.u2

Fair Value Measurements - Financial Instruments (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Financial Instruments |  |
Cash and cash equivalents | $ 285 | $ 580
Short-term investments | 0 | 17
Book Value |  |
Financial Instruments |  |
Cash and cash equivalents | 285 | 580
Short-term investments | 0 | 17
Book Value | Retail |  |
Financial Instruments |  |
Long-term debt | 917 | 917
Book Value | Institutional |  |
Financial Instruments |  |
Long-term debt | 534 | 534
Book Value | Other |  |
Financial Instruments |  |
Long-term debt | 83 | 180
Fair Value | Level 1 |  |
Financial Instruments |  |
Cash and cash equivalents | 285 | 580
Short-term investments | 0 | 17
Fair Value | Level 2 | Retail |  |
Financial Instruments |  |
Long-term debt | 943 | 850
Fair Value | Level 2 | Institutional |  |
Financial Instruments |  |
Long-term debt | 594 | 531
Fair Value | Level 2 | Other |  |
Financial Instruments |  |
Long-term debt | $ 83 | $ 180
7.25% 2063 Senior Notes |  |
Financial Instruments |  |
Interest rate on debt | 7.25% |
7.25% 2064 Senior Notes |  |
Financial Instruments |  |
Interest rate on debt | 7.25% |
6.95% Senior Notes |  |
Financial Instruments |  |
Interest rate on debt | 6.95% |
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 | 3.55% | 5.03%
Interest rate | Maximum | Institutional and Other |  |
Financial Instruments |  |
Fair value assumption, interest rate | 5.73% | 6.97%

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