Investments - Portfolio composition (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Investments [Abstract]
Fixed income securities, at fair value	$ 17,937	$ 23,907
Mortgage loans, net	2,951	3,359
Equity securities, at fair value	11	1,536
Limited partnership interests	1,348	3,065
Short-term investments, at fair value	1,035	974
Policy loans	525	582
Other, net	1,382	1,375
Total investments	$ 25,189	$ 34,798

Amount 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).

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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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Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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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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