Fair Value Measurements - Financial Instruments Not Carried At Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	$ 151,552	$ 151,739
Assets, fair value	108,076	106,389
Liabilities	150,490	150,479
Carrying amount \| Other policyholder funds and benefits payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	9,921	10,675
Carrying amount \| Funds Withheld Liability
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	10,367	11,034
Carrying amount \| Policy loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	1,528	1,495
Carrying amount \| Mortgage loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	2,019	2,520
Estimate of fair value \| Other policyholder funds and benefits payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	8,305	8,666
Estimate of fair value \| Funds Withheld Liability
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	10,367	11,034
Estimate of fair value \| Policy loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	1,528	1,495
Estimate of fair value \| Mortgage loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	$ 1,814	$ 2,232

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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