Investments (Net Investment Gains Losses - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Debt Securities, Available-for-sale [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	$ (222)	$ 348	$ (769)	$ 1,000
Equity Securities, FV-NI, Unrealized Gain (Loss)	(26)	(6)	(88)	158
Net investment gains (losses)	(414)	(84)	(1,617)	1,655
Foreign Currency Transaction Gain (Loss), Realized	(67)	(23)	(81)	(4)
Metropolitan Property and Casualty Insurance Company
Debt Securities, Available-for-sale [Line Items]
Gain (Loss) on Disposition of Business		1,400		1,400
Equity Securities
Debt Securities, Available-for-sale [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	(25)	(16)	(87)	86
Cash Flow Hedging [Member]
Debt Securities, Available-for-sale [Line Items]
Net investment gains (losses)	(25)	3	25	43
Foreign Currency Gain (Loss) [Member] \| Reclassification out of Accumulated Other Comprehensive Income \| Cash Flow Hedging [Member]
Debt Securities, Available-for-sale [Line Items]
Net investment gains (losses)	$ (15)	$ 6	$ 45	$ 54

Amount of realized gain (loss) on investment in debt and equity securities.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Amount of realized and unrealized gain (loss) on investment.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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