Fair Value - Schedule of Fair Value Measurement Inputs and Valuation Techniques (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	$ 9,295	$ 9,203
Interest rate & other derivative — non-qualifying hedges	110	0
Interest rate & other derivative — non-qualifying hedges	204	0
Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	9,295	9,203
Interest rate & other derivative — non-qualifying hedges	110
Interest rate & other derivative — non-qualifying hedges	204
Fair Value, Recurring \| Corporate bonds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	586	608
Fair Value, Recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds	186	207
Interest rate & other derivative — non-qualifying hedges	1
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	$ 186	$ 207

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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