v3.19.1

Debt (First Lien Term Loans) (Details) - USD ($) $ in Millions | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Debt Instrument [Line Items] |  |
Long-term Debt | $ 10,682 | $ 10,156
New 2019 First Lien Term Loan [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | 389 | 389
2023 First Lien Term Loan [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | 1,057 | 1,059
2024 First Lien Term Loan [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | 1,526 | 1,528
First Lien Term Loans [Member] |  |
Debt Instrument [Line Items] |  |
Long-term Debt | $ 2,972 | $ 2,976

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