Investments - Portfolio composition (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Investments [Abstract]
Fixed income securities, at fair value	$ 44,103	$ 42,485
Equity securities, at fair value	2,174	4,567
Mortgage loans, net	781	762
Limited partnership interests	7,971	8,114
Short-term investments, at fair value	6,722	4,173
Other investments, net	1,724	1,728
Total investments	$ 63,475	$ 61,829

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amount of investments classified as other.

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Amount of short-term investments classified as other.

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