Name:	met_CashCollateralPaid
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Cumulative net cash outflow paid to the unaffiliated financial institution as a result of continued fluctuation in the estimated fair value of the debt instrument as of the balance sheet date.

No definition available.

Name:	met_CashCollateralPaidCumulativeNet
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Debt Instrument, Term in Years.

No definition available.

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

No definition available.

Name:	met_InvestedAssetsOnDepositHeldInTrustAndPledgedAsCollateral
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Data Type:	num:percentItemType
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Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Subparagraph (SX 210.5-02.22(a)(1))

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The increase (decrease) during the reporting period in other amounts due to the reporting entity, which are not otherwise defined in the taxonomy.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of the cost of borrowed funds accounted for as interest expense.

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-Publisher FASB

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-Topic 835

-SubTopic 20

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-Topic 942

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-Subparagraph (SX 210.9-04.9)

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The fair value, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of other debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 860

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Data Type:	xbrli:monetaryItemType
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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

No definition available.

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Name:	dei_LegalEntityAxis=met_MetLifeReinsuranceCompanyOfCharlestonMember
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Name:	dei_LegalEntityAxis=us-gaap_ParentCompanyMember
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Name:	met_CumulativeRepaymentAxis=met_CumulativeRepaymentMember
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Name:	met_TransferAssetsHeldInTrustAxis=met_TransferAssetsHeldInTrustMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=met_SecuredDebtMrcMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=met_SecuredDebtMrscMember
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