Derivative Financial Instruments - Narrative (Details) $ in Millions	6 Months Ended
Jun. 30, 2023 USD ($) contract	Dec. 31, 2022 USD ($) contract
All Counterparties Except Merrill Lynch
Derivative [Line Items]
Counterparties, collateral required threshold	0.00%
Embedded derivatives
Derivative [Line Items]
Term of contract, term one	1 year
Term of contract, term two	2 years
Term of contract, term three	3 years
Term of contract, term four	5 years
Call options \| Not Designated as Hedging Instrument
Derivative [Line Items]
Collateral posted	$ 579	$ 219
Maximum amount of loss due to credit risk	81	33
Call options \| Derivatives for Trading and Investment \| Not Designated as Hedging Instrument
Derivative [Line Items]
Collateral posted	579	219
Maximum amount of loss due to credit risk	81	33
Call options \| Cash and Cash Equivalents \| Not Designated as Hedging Instrument
Derivative [Line Items]
Collateral posted	$ 459	$ 178
Futures contracts
Derivative [Line Items]
Number of instruments held \| contract	409,000,000	409,000,000
Collateral held	$ 4	$ 3

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Derivatives, Collateral, Net Exposure Threshold for Which Collateral Required

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The number of derivative instruments of a particular group held by the entity.

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