Investments (Net Investment Gains Losses - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt Securities, Available-for-sale [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	$ (405)	$ 528	$ (547)	$ 698
Equity Securities, FV-NI, Unrealized Gain (Loss)	(42)	57	(62)	164
Net investment gains (losses)	(685)	1,605	(1,203)	1,739
Foreign Currency Transaction Gain (Loss), Realized	(137)	10	(14)	19
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)	(40)	50	(62)	113
Cash Flow Hedging [Member]
Debt Securities, Available-for-sale [Line Items]
Net investment gains (losses)	34	19	50	40
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)	$ 42	$ 19	$ 60	$ 48

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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