Condensed Financial Information (Parent Company) (Support Agreements - Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Condensed Financial Statements, Captions [Line Items]
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 19	$ 25
Parent Company \| Support Agreement Exeter Obligations [Member]
Condensed Financial Statements, Captions [Line Items]
Amount guaranteed under support agreement	$ 1,000
Parent Company \| Support Agreement MetLife Reinsurance Company of Vermont [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	200
Parent Company \| Support Agreement MetLife Reinsurance Company of Charleston [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	200
Parent Company \| Support Agreement - Guarantees of Subsidiary Derivative Obligations [Member]
Condensed Financial Statements, Captions [Line Items]
Derivative Assets, Fair Value, Net	$ 27	174
Unsecured derivative liability positions guaranteed by MetLife, Inc.	191	181
Estimated fair value of collateral provided to counterparties by the subsidiaries	183	181
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 8	$ 0

The amount of obligations supported under the issued support agreement.

No definition available.

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- Definition

Disclosure of the guaranteed minimum level of regulatory based total adjusted capital level for entity in domestic jurisdiction.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 04
-Paragraph a
-Publisher SEC

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-Topic 235
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-Name Accounting Standards Codification
-Section S99
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- Definition

Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 55
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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative not subject to master netting arrangement or similar agreement.

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