Fair Value - Fair Value of Long Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Term loans and senior notes | Carrying Amount | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	$ 5,121	$ 5,179
Term loans and senior notes | Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	4,641	5,113
Other Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	$ 169	$ 192