The aggregate amount of obligations supported under the issued support agreement.

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- Definition

The cash outflow associated with the amount paid to the subsidiaries during the period.

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- Definition

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

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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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No definition available.

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- Definition

Fair value of the gross assets less the gross liabilities of a derivative asset or group of derivative assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The amount as of the balance sheet date of the fair value of derivative liabilities that in accordance with the entity's accounting policy was not offset against the right to reclaim cash collateral under a master netting arrangement.

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Fair value of the gross liabilities less the gross assets of a derivative liability or group of derivative liabilities.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 505

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-Paragraph 1

-Subparagraph (b)

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Condensed Financial Information (Parent Company) (Details Textuals 3) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Mitsui Sumitomo MetLife Insurance Co., LTD. ("MSI MetLife") [Member]
Condensed Financial Statements, Captions [Line Items]
Interest in Mitsui Sumitomo MetLife Insurance Co., LTD. ("MSI MetLife")		50.00%
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Capital contributions to subsidiaries	$ (1,223,000,000)	$ (1,439,000,000)	$ (374,000,000)
Parent Company [Member] \| Support Agreement MetLife Bank [Member]
Condensed Financial Statements, Captions [Line Items]
Capital contributions to subsidiaries	34,000,000
Parent Company [Member] \| Support Agreement Exeter Obligations [Member]
Condensed Financial Statements, Captions [Line Items]
Aggregate obligation amount guaranteed under support agreement	1,000,000,000
Parent Company [Member] \| Support Agreement MetLife Reinsurance Company of Vermont [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	equal to or greater than 200% of authorized control level risk-based capital
Parent Company [Member] \| Support Agreement MetLife Reinsurance Company of Charleston [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	equal to or greater than 200% of the company action level risk-based capital
Parent Company [Member] \| Support Agreement MetLife Reinsurance Company of South Carolina [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	equal to or greater than 100% of authorized control level risk-based capital
Minimum capital and surplus	250,000
Parent Company [Member] \| Support Agreement MetLife Investors Insurance Company and First MetLife Investors Insurance Company [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	equal to or greater than 150% of the company action level risk-based capital
Minimum capital and surplus	10,000,000
Parent Company [Member] \| Support Agreement MetLife Reinsurance Company of Delaware [Member]
Condensed Financial Statements, Captions [Line Items]
Guaranteed adjusted capital levels	equal to or greater than 200% of the company action level risk-based capital
Parent Company [Member] \| Support Agreement - Guarantees of Subsidiary Derivative Obligations [Member]
Condensed Financial Statements, Captions [Line Items]
Derivative Assets, Fair Value, Net	3,200,000,000	4,900,000,000
Derivative Liabilities, Fair Value, Net	22,000,000	51,000,000
Estimated fair value of collateral provided to counterparties by the subsidiaries	12,000,000	47,000,000
Unsecured derivative liability positions guaranteed by MetLife, Inc.	$ 10,000,000	$ 4,000,000