Fair Value - Schedule of Fair Value Measurement Inputs and Valuation Techniques (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	$ 9,210	$ 9,203
Interest rate & other derivative — non-qualifying hedges	80	3
Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	9,210	9,203
Interest rate & other derivative — non-qualifying hedges	80
Fair Value, Recurring | Corporate bonds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	570	608
Fair Value, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	180	207
Interest rate & other derivative — non-qualifying hedges	1
Fair Value, Recurring | Level 3 | Corporate bonds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	$ 180	$ 207