Investments (Real Estate and Real Estate Joint Ventures) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Real Estate [Line Items]
Leased real estate investments, Carrying Value	$ 4,446	$ 4,523
Other real estate investments, Carrying Value	507	487
Real estate joint ventures, Carrying Value	8,379	8,127
Real Estate Investments, Net	13,332	13,137
Income (Loss) from Equity Method Investments	151	1,305	$ 5,136
Real Estate and Real Estate Joint Ventures
Real Estate [Line Items]
Gross Investment Income, Operating	$ 438	$ 1,200	$ 954
Leased real estate
Real Estate [Line Items]
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Other real estate
Real Estate [Line Items]
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Real estate joint ventures
Real Estate [Line Items]
Income (Loss) from Equity Method Investments	$ (225)	$ 556	$ 326

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount of real estate investments, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; (7) other real estate investments; (8) real estate joint ventures; and (9) unconsolidated real estate and other joint ventures not separately presented.

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The book value of investments in real estate joint ventures including direct and indirect investments.

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Amount of real estate owned for income production and capital accretion potential, not otherwise specified in the existing taxonomy. Such real estate excludes that which is occupied or used in the business, for entertainment purposes, or held in inventory for specific purposes.

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Carrying amount of income producing properties held for rental.

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