Name:	met_SupplementaryInsuranceInformationPolicyholderBenefitsAndInterestCredited
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Sum of premiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers, and income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products. May also include an entity's proportionate share of the income or loss before extraordinary items and other adjustments from its investments in: unconsolidated subsidiaries, associated companies, and corporate joint ventures, unincorporated joint ventures, general partnerships, and limited partnerships over which the entity exercises significant influence that are principally engaged in insurance underwriting, reinsurance, or insurance sales activities.

No definition available.

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Amount of actual written premiums excluding premiums associated with life insurance policies. These should include premiums from reinsurance assumed and should be net of premiums on reinsurance ceded.

No definition available.

Name:	met_SupplementaryInsuranceInformationPremiumsWrittenExcludingLife
Namespace Prefix:	met_
Data Type:	xbrli:monetaryItemType
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The amount of DAC and capitalized present value of future profits (also known as VOBA) that was amortized during the period, generally in proportion to related revenue earned, estimated gross profits, or over the customer relationship or some other period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section S99

-Paragraph 2

-Subparagraph (2)

-URI http://asc.fasb.org/extlink&oid=6784649&loc=d3e569990-122904

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 60

-Paragraph 60

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 92-9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6967983&loc=d3e11264-158415

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The income earned from investments in securities and property, equipment and other capital assets. It includes rent from property and equipment, dividends from shares in corporations, and interest from bonds, loans, mortgages, derivatives, commercial paper, bank accounts, certificates of deposits, treasuries, and other financial securities. It does not include realized gains and losses on investments.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 2

-Article 7

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.2)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of other operating expense incurred.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-16)

-URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574960-122915