Derivative Financial Instruments - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2024 USD ($) contract counterparty	Dec. 31, 2023 USD ($) contract
Derivative [Line Items]
Number of counterparties, net exposure threshold set to zero \| counterparty	1
Counterparties, collateral required threshold	0.00%
Other 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 five	5 years
Term of contract, term six	6 years
Call options and interest rate swaps \| Derivatives for Trading and Investment \| Not Designated as Hedging Instrument
Derivative [Line Items]
Collateral posted	$ 1,351	$ 775
Net Credit Risk	53	39
Call options and interest rate swaps \| Cash and Cash Equivalents \| Not Designated as Hedging Instrument
Derivative [Line Items]
Collateral posted	$ 1,133	$ 588
Futures contracts
Derivative [Line Items]
Number of instruments held \| contract	392	439
Collateral held	$ 5	$ 4

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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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