Condensed Financial Information (Parent Company) (Support Agreements - Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Condensed Financial Statements, Captions [Line Items]
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 108,000,000	$ 25,000,000
Parent Company \| Support Agreement Exeter Obligations [Member]
Condensed Financial Statements, Captions [Line Items]
Amount guaranteed under support agreement	$ 1,000,000,000.0
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	$ 366,000,000	360,000,000
Unsecured derivative liability positions guaranteed by MetLife, Inc.	158,000,000	197,000,000
Estimated fair value of collateral provided to counterparties by the subsidiaries	158,000,000	196,000,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 0	$ 1,000,000

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.

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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

No definition available.

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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

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- Definition

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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- Definition

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 effects of master netting arrangements, 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 offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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