Debt - Senior Notes (Details) - USD ($) |
3 Months Ended | 9 Months Ended | ||||||
---|---|---|---|---|---|---|---|---|
Sep. 30, 2019 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Feb. 28, 2019 |
Dec. 31, 2018 |
Jul. 31, 2018 |
|
Debt Instrument [Line Items] | ||||||||
Debt extinguishment loss | $ 0 | $ 17,000,000 | $ 10,000,000 | $ 5,000,000 | $ 27,000,000 | |||
6.75% Senior notes due 2024 | ||||||||
Debt Instrument [Line Items] | ||||||||
Debt instrument face amount | $ 1,000,000,000.0 | |||||||
Stated interest rate | 6.75% | 6.75% | 6.75% | |||||
Long-term debt, principal balance | $ 1,000,000,000 | $ 1,000,000,000 | $ 0 | |||||
Senior Notes Due 2022 | ||||||||
Debt Instrument [Line Items] | ||||||||
Stated interest rate | 6.50% | 6.50% | ||||||
Long-term debt, principal balance | $ 1,200,000,000 | $ 1,200,000,000 | $ 1,200,000,000 | |||||
Senior Notes | Senior Notes Due 2022 | ||||||||
Debt Instrument [Line Items] | ||||||||
Repurchase amount | $ 400,000,000 | |||||||
Long-term debt, principal balance | $ 1,600,000,000 | |||||||
Debt extinguishment loss | $ 17,000,000 |