The element presents the invested assets on deposit, held in trust and pledged as collateral.

No definition available.

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Namespace Prefix:	met_
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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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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.

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- Definition

Amount of increase (decrease) in receivables classified as other.

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- Definition

Amount due from parties in nontrade transactions, classified as other.

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- Definition

The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

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- Details

Name:	srt_ConsolidatedEntitiesAxis=srt_ParentCompanyMember
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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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Period Type:

- Details

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Period Type:

Collateral Financing Arrangements Collateral Financing Arrangements (Associated with Closed Block) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2007
Debt Instrument [Line Items]
Invested assets pledged as collateral	$ 26,017	$ 25,442
Parent Company [Member] \| Secured Debt Mrc [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate Terms	compounded SOFR calculated in arrears plus a spread adjustment of 0.26161%			three-month LIBOR plus 1.12%
Met Life Reinsurance Company Of Charleston [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Principal Outstanding	$ 637	716
Other Receivables	85	93
Invested Assets On Deposit Held In Trust And Pledged As Collateral	1,397	1,369
Increase (Decrease) in Other Receivables	8	7	$ 10
Invested assets pledged as collateral	$ 10	$ 43