v3.19.2

Debt (First Lien Notes) (Details) - USD ($) $ in Millions | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Debt Instrument [Line Items] |  |
Long-term Debt | $ 10,677 | $ 10,156
2022 First Lien Notes [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | 744 | 743
2024 First Lien Notes [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | 487 | 486
2026 First Lien Notes [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | 1,171 | 1,171
Corporate Debt Securities [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | $ 2,402 | $ 2,400

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