Investments (Real Estate and Real Estate Joint Ventures) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Real Estate [Line Items]
Leased real estate investments, Carrying Value	$ 4,536		$ 4,536		$ 4,446
Other real estate investments, Carrying Value	687		687		507
Real estate joint ventures, Carrying Value	8,508		8,508		8,379
Real Estate Investments, Net	13,731		13,731		$ 13,332
Income (Loss) from Equity Method Investments	201	$ 95	687	$ 174
Real Estate and Real Estate Joint Ventures
Real Estate [Line Items]
Gross Investment Income, Operating	178	96	268	259
Leased real estate
Real Estate [Line Items]
Operating Lease, Lease Income	$ 88	$ 89	$ 255	$ 271
Operating Lease, Lease Income	Revenues	Revenues	Revenues	Revenues
Other real estate
Real Estate [Line Items]
Operating Lease, Lease Income	$ 79	$ 71	$ 204	$ 206
Operating Lease, Lease Income		Revenues	Revenues	Revenues
REJV
Real Estate [Line Items]
Income (Loss) from Equity Method Investments	$ 11	$ (64)	$ (191)	$ (218)

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 income (loss) for proportionate share of equity method investee's income (loss).

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Indicates line item in statement of income or comprehensive income that includes operating lease income.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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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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