Fair Value - Fair Value of Long Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
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	$ 5,094	$ 5,153
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	5,159	5,138
Other Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	$ 141	$ 180