Investments (Details 15) (USD $) In Millions	6 Months Ended
	Jun. 30, 2011
Changes in net unrealized investment gains (losses) included in accumulated other comprehensive loss
Balance, beginning of period	$ 2,990
Fixed maturity securities on which noncredit OTTI losses have been recognized	(138)
Unrealized investment gains (losses) during the year	3,741
Unrealized investment gains (losses) relating to [Abstract]
Insurance liability gain (loss) recognition	(389)
DAC and VOBA related to noncredit OTTI losses recognized in accumulated other comprehensive income (loss)	(4)
DAC and VOBA	(225)
Policyholder dividend obligation	(405)
Deferred income tax benefit (expense) related to noncredit OTTI losses recognized in accumulated other comprehensive income (loss)	48
Deferred income tax benefit (expense)	(959)
Net unrealized investment gains (losses)	4,659
Net unrealized investment gains (losses) attributable to noncontrolling interests	5
Balance, end of period	4,664
Changes in net unrealized investment gains (losses)	1,669
Changes in net unrealized investment gains (losses) attributable to noncontrolling interests	5
Changes in net unrealized investment gains (losses) attributable to MetLife, Inc.	$ 1,674