Consolidated Statements of Operations and Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues
Premiums	$ 10,876	$ 9,839	$ 29,421	$ 27,956
Universal life and investment-type product policy fees	1,428	1,341	4,152	4,127
Net investment income	4,295	4,609	12,909	12,527
Other revenues	301	356	935	1,309
Net investment gains (losses):
Other-than-temporary impairments on fixed maturity securities	(6)	(4)	(8)	(74)
Other-than-temporary impairments on fixed maturity securities transferred to other comprehensive income (loss)	1	(5)	1	(9)
Other net investment gains (losses)	(601)	240	(432)	681
Total net investment gains (losses)	(606)	231	(439)	598
Net derivative gains (losses)	(190)	(543)	(663)	1,438
Total revenues	16,104	15,833	46,315	47,955
Expenses
Policyholder benefits and claims	10,645	9,612	28,923	27,394
Interest credited to policyholder account balances	1,338	1,544	4,081	3,819
Policyholder dividends	302	302	925	924
Other expenses	3,318	3,216	9,904	10,296
Total expenses	15,603	14,674	43,833	42,433
Income (loss) from continuing operations before provision for income tax	501	1,159	2,482	5,522
Provision for income tax expense (benefit)	(392)	135	(148)	1,253
Income from continuing operations, net of income tax	893	1,024	2,630	4,269
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(968)	(451)	(989)	(1,379)
Net income (loss)	(75)	573	1,641	2,890
Less: Net income (loss) attributable to noncontrolling interests	6	(4)	12	2
Net income (loss) attributable to MetLife, Inc.	(81)	577	1,629	2,888
Less: Preferred stock dividends	6	6	58	58
Net income (loss) available to MetLife, Inc.’s common shareholders	(87)	571	1,571	2,830
Comprehensive income (loss)	(182)	(463)	4,623	11,809
Less: Comprehensive income (loss) attributable to noncontrolling interests, net of income tax	10	(3)	16	97
Comprehensive income (loss) attributable to MetLife, Inc.	$ (192)	$ (460)	$ 4,607	$ 11,712
Income (loss) from continuing operations, net of income tax, available to MetLife, Inc's common shareholders per common share: [Abstract]
Basic	$ 0.83	$ 0.93	$ 2.38	$ 3.82
Diluted	0.82	0.92	2.36	3.80
Net income (loss) available to MetLife, Inc.’s common shareholders per common share:
Net income (loss) available to MetLife, Inc.’s common shareholders per common share:	(0.08)	0.52	1.46	2.57
Basic	(0.08)	0.51	1.45	2.55
Diluted	$ 0.400	$ 0.400	$ 1.200	$ 1.175