v3.19.3.a.u2

Debt Debt Repurchases (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Debt Instrument, Redemption [Line Items] |  |  |  |
Gains (Losses) on Extinguishment of Debt |  | $ (58) | $ 28 | $ (38)
Senior Unsecured Notes 2023 [Member] |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |
Debt Instrument, Repurchased Face Amount | $ 0 | 0 | 14 |
Debt Instrument, Repurchase Amount | 0 | 0 | 13 |
Gains (Losses) on Extinguishment of Debt | 24 | 0 | 1 |
Write off of Deferred Debt Issuance Cost | 6 |  |  |
Unsecured Debt [Member] |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |
Debt Instrument, Repurchased Face Amount | 160 | 160 | 390 |
Debt Instrument, Repurchase Amount | 158 | 158 | 355 |
Gains (Losses) on Extinguishment of Debt |  | 2 | 35 |
Write off of Deferred Debt Issuance Cost |  |  | 3 |
Senior Unsecured Notes 2024 [Member] |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |
Debt Instrument, Repurchased Face Amount | 122 | 122 | 46 |
Debt Instrument, Repurchase Amount | 123 | 123 | 42 |
Gains (Losses) on Extinguishment of Debt |  | (1) | 4 |
Senior Unsecured Notes 2025 [Member] |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |
Debt Instrument, Repurchased Face Amount | 38 | 38 | 330 |
Debt Instrument, Repurchase Amount | $ 35 | 35 | 300 |
Gains (Losses) on Extinguishment of Debt |  | $ 3 | $ 30 |

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