v3.19.3
Debt (First Lien Term Loans) (Details) - USD ($)
$ in Millions
Sep. 30, 2019
Dec. 31, 2018
Debt Instrument [Line Items]    
Long-term Debt $ 10,709 $ 10,156
New 2019 First Lien Term Loan [Member]    
Debt Instrument [Line Items]    
Long-term Debt 0 389
2023 First Lien Term Loan [Member]    
Debt Instrument [Line Items]    
Long-term Debt 0 1,059
2024 First Lien Term Loan [Member]    
Debt Instrument [Line Items]    
Long-term Debt 1,519 1,528
2026 First Lien Term Loans [Member]    
Debt Instrument [Line Items]    
Long-term Debt 1,656 0
First Lien Term Loans [Member]    
Debt Instrument [Line Items]    
Long-term Debt $ 3,175 $ 2,976