Discontinued Operations (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Discontinued Operations in Consolidated Statements of Operations and Consolidated Balance Sheets
Total revenues	$ 17,150	$ 14,138	$ 33,061	$ 27,237
Total expenses	15,430	11,775	29,859	23,690
Provision for income tax expense (benefit)	519	827	947	1,183
Net investment gain (loss), net of income tax	(32)	132	(8)	256
Income (loss) from discontinued operations, net of income tax	29	11	(12)	17
Total assets held-for-sale	3,369		3,369		3,331
Total liabilities held-for-sale	3,163		3,163		3,043
Major classes of assets and liabilities included above:
Total investments	482,170		482,170		460,306
Total future policy benefits	176,353		176,353		170,912
Discontinued Operations (Textuals) [Abstract]
Income (loss) from discontinued operations, net of income tax	29	11	(12)	17
Met Life Taiwan Insurance Company Limited [Member]
Discontinued Operations in Consolidated Statements of Operations and Consolidated Balance Sheets
Total revenues	129	105	236	194
Total expenses	116	100	214	184
Income before provision for income tax	13	5	22	10
Provision for income tax expense (benefit)	5	1	8	3
Income from operations of discontinued operations, net of income tax	8	4	14	7
Net investment gain (loss), net of income tax	(7)	0	(74)	0
Income (loss) from discontinued operations, net of income tax	1	4	(60)	7
Total assets held-for-sale	3,369		3,369		3,331
Total liabilities held-for-sale	3,163		3,163		3,043
Major classes of assets and liabilities included above:
Total investments	2,987		2,987		2,726
Total future policy benefits	2,616		2,616		2,461
Discontinued Operations (Textuals) [Abstract]
Income (loss) from discontinued operations, net of income tax	1	4	(60)	7
Real Estate [Member]
Discontinued Operations in Consolidated Statements of Operations and Consolidated Balance Sheets
Income (loss) from discontinued operations, net of income tax	28	7	48	10
Discontinued Operations (Textuals) [Abstract]
Real Estate Held-for-sale	7		7		65
Income (loss) from discontinued operations, net of income tax	$ 28	$ 7	$ 48	$ 10

Discontinued Operations.

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Major Classes Of Assets And Liabilities.

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Operations Of Subsidiary Reflected As Discontinued Operations.

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The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for assets of a disposal group, including a component of the entity (discontinued operation), to be sold or that has been disposed of through sale, as of the financial statement date.

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The total amount of expense recognized during the period for future policy benefits, claims and claims adjustment costs, and for selling, general and administrative costs.

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-Name Regulation S-X (SX)
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Pretax income (loss) from operations of a business component (exclusive of any gain or loss on disposal, or provision therefore) during the reporting period, until its disposal.

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After tax income (loss) from operations of a business component (exclusive of any gain or loss on disposal, or provision therefore) during the reporting period, until its disposal.

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The difference between the book value and the sale price of other nonspecific investments. This element is used when other, more specific, elements are not appropriate. This element refers to the gain (loss) included in earnings.

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This element represents the overall income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items and the cumulative effect of accounting changes before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations.

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Sum of the carrying amounts as of the balance sheet date of current and noncurrent investments.

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The obligations arising from the sale, disposal, or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

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The sum of the known and estimated amounts payable as of the balance sheet date to policyholders pertaining to insured events for long-duration contracts, which can be viewed as either (a) the present value of future benefits to be paid to or on behalf of policyholders and expenses less the present value of future net premiums payable under the insurance contracts or (b) the accumulated amount of net premiums already collected less the accumulated amount of benefits and expenses already paid to or on behalf of policyholders.

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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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