Debt - Prior Term Loan Facility (Details) - USD ($) |
Sep. 30, 2020 |
Dec. 31, 2019 |
Dec. 22, 2017 |
Nov. 30, 2016 |
|---|---|---|---|---|
| Debt Instrument [Line Items] | ||||
| Long-term debt, gross | $ 3,585,200,000 | |||
| Term Loan due 2023 | Revolving Credit Facility | ||||
| Debt Instrument [Line Items] | ||||
| Aggregate principal amount | $ 325,000,000.0 | $ 2,320,000,000.0 | ||
| Long-term debt, gross | $ 0 | $ 2,070,000,000.0 |