Investments (Details 15) (USD $) In Millions	9 Months Ended
Sep. 30, 2011
Changes In Net Unrealized Investment Gains Losses Included In Accumulated Other Comprehensive Loss [Abstract]
Balance, beginning of period	$ 2,990
Fixed maturity securities on which noncredit OTTI losses have been recognized	(77)
Unrealized investment gains (losses) during the year	14,360
Unrealized investment gains (losses) relating to [Abstract]
Insurance liability gain (loss) recognition	(3,274)
DAC and VOBA related to noncredit OTTI losses recognized in accumulated other comprehensive income (loss)	3
DAC and VOBA	(865)
Policyholder dividend obligation	(1,906)
Deferred income tax benefit (expense) related to noncredit OTTI losses recognized in accumulated other comprehensive income (loss)	23
Deferred income tax benefit (expense)	(2,812)
Net unrealized investment gains (losses)	8,442
Net unrealized investment gains (losses) attributable to noncontrolling interests	5
Balance, end of period	8,447
Changes in net unrealized investment gains (losses)	5,452
Changes in net unrealized investment gains (losses) attributable to noncontrolling interests	5
Changes in net unrealized investment gains (losses) attributable to MetLife, Inc.	$ 5,457

This item presents the increase (decrease) in net unrealized investment gains (losses) attributable to the Company.

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This item presents the increase (decrease) in net unrealized investment gains (losses) attributable to noncontrolling interests.

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This item presents the increase (decrease) in net unrealized investment gains (losses) excluding portion attributable to noncontrolling interests.

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This item presents the increase (decrease) in net unrealized investment gains (losses) related to DAC and VOBA.

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Changes in net unrealized investment gains (losses) related to DAC and VOBA related noncredit OTTI losses recognized in other comprehensive income (loss).

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This item presents the increase (decrease) in net unrealized investment gains (losses) on fixed maturity securities on which noncredit OTTI losses have been recognized.

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Changes in net unrealized investment gains (losses) related to deferred income tax benefit (expense) related to noncredit OTTI losses recognized in other comprehensive income (loss).

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This item presents the increase (decrease) in net unrealized investment gains (losses) related to insurance liability gain (loss) recognition.

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This item presents the increase (decrease) in net unrealized investment gains (losses) related to policyholder dividend obligation.

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This item presents the net unrealized investment gains (losses) attributable to noncontrolling interests.

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This item presents the net unrealized investment gains (losses) excluding the portion attributable to noncontrolling interests.

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This item presents net unrealized investment gains (losses) attributable to the Company.

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Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities during the period being reported (except when designated as a fair value hedge).

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Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

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