Segment Information (Earnings) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues
Premiums	$ 9,935	$ 9,417	$ 19,250	$ 19,110
Universal life and investment-type product policy fees	2,302	2,286	4,604	4,630
Net investment income	4,959	4,887	10,155	9,446
Other revenues	382	487	756	974
Net investment gains (losses)	104	266	112	281
Net derivative gains (losses)	(437)	(2,099)	(1,363)	(764)
Total revenues	17,245	15,244	33,514	33,677
Expenses
Policyholder benefits and claims and policyholder dividends	10,622	10,598	20,798	20,591
Interest credited to policyholder account balances	1,562	1,500	3,274	2,826
Capitalization of DAC	(821)	(915)	(1,617)	(1,896)
Amortization of DAC and VOBA	704	121	1,237	1,116
Amortization of negative VOBA	(38)	(67)	(81)	(166)
Interest expense on debt	295	306	591	618
Other expenses	3,919	3,801	7,493	7,766
Total expenses	16,243	15,344	31,695	30,855
Provision for income tax expense (benefit)	115	(214)	103	505
Net income (loss)	887	114	1,716	2,317
Operating Segments
Revenues
Premiums	9,935	9,417	19,250	18,684
Universal life and investment-type product policy fees	2,191	2,173	4,392	4,324
Net investment income	4,884	4,881	9,879	9,587
Other revenues	377	484	745	971
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	17,387	16,955	34,266	33,566
Expenses
Policyholder benefits and claims and policyholder dividends	10,350	10,385	20,178	19,978
Interest credited to policyholder account balances	1,349	1,314	2,659	2,615
Capitalization of DAC	(821)	(915)	(1,617)	(1,791)
Amortization of DAC and VOBA	844	1,015	1,689	1,896
Amortization of negative VOBA	(35)	(61)	(75)	(128)
Interest expense on debt	294	303	590	615
Other expenses	3,576	3,659	7,044	7,369
Total expenses	15,557	15,700	30,468	30,554
Provision for income tax expense (benefit)	377	285	793	707
Operating earnings	1,453	970	3,005	2,305
Operating Segments | U.S.
Revenues
Premiums	5,877	5,171	11,062	10,191
Universal life and investment-type product policy fees	251	248	516	498
Net investment income	1,575	1,565	3,187	3,025
Other revenues	199	193	403	397
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	7,902	7,177	15,168	14,111
Expenses
Policyholder benefits and claims and policyholder dividends	5,878	5,270	11,113	10,316
Interest credited to policyholder account balances	359	323	710	645
Capitalization of DAC	(116)	(121)	(216)	(232)
Amortization of DAC and VOBA	114	118	228	236
Amortization of negative VOBA	0	0	0	0
Interest expense on debt	4	3	6	5
Other expenses	914	918	1,823	1,860
Total expenses	7,153	6,511	13,664	12,830
Provision for income tax expense (benefit)	250	223	502	432
Operating earnings	499	443	1,002	849
Operating Segments | Asia
Revenues
Premiums	1,659	1,681	3,367	3,339
Universal life and investment-type product policy fees	375	370	741	720
Net investment income	729	678	1,431	1,296
Other revenues	11	16	21	33
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	2,774	2,745	5,560	5,388
Expenses
Policyholder benefits and claims and policyholder dividends	1,247	1,324	2,562	2,560
Interest credited to policyholder account balances	333	324	654	643
Capitalization of DAC	(428)	(426)	(848)	(811)
Amortization of DAC and VOBA	290	304	581	590
Amortization of negative VOBA	(30)	(57)	(67)	(121)
Interest expense on debt	0	0	0	0
Other expenses	895	877	1,770	1,728
Total expenses	2,307	2,346	4,652	4,589
Provision for income tax expense (benefit)	157	140	303	235
Operating earnings	310	259	605	564
Operating Segments | Latin America
Revenues
Premiums	645	631	1,292	1,232
Universal life and investment-type product policy fees	275	269	535	537
Net investment income	289	243	592	498
Other revenues	8	8	17	15
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	1,217	1,151	2,436	2,282
Expenses
Policyholder benefits and claims and policyholder dividends	596	583	1,229	1,133
Interest credited to policyholder account balances	94	84	176	164
Capitalization of DAC	(88)	(80)	(170)	(153)
Amortization of DAC and VOBA	68	66	146	129
Amortization of negative VOBA	0	0	0	0
Interest expense on debt	2	0	3	0
Other expenses	357	323	683	633
Total expenses	1,029	976	2,067	1,906
Provision for income tax expense (benefit)	34	38	72	88
Operating earnings	154	137	297	288
Operating Segments | EMEA
Revenues
Premiums	505	519	1,007	1,019
Universal life and investment-type product policy fees	92	95	187	190
Net investment income	78	83	152	163
Other revenues	28	19	45	39
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	703	716	1,391	1,411
Expenses
Policyholder benefits and claims and policyholder dividends	270	283	539	544
Interest credited to policyholder account balances	25	30	49	59
Capitalization of DAC	(100)	(106)	(192)	(207)
Amortization of DAC and VOBA	95	103	182	205
Amortization of negative VOBA	(5)	(4)	(8)	(7)
Interest expense on debt	0	0	0	0
Other expenses	332	336	648	669
Total expenses	617	642	1,218	1,263
Provision for income tax expense (benefit)	14	10	26	21
Operating earnings	72	64	147	127
Operating Segments | MetLife Holdings
Revenues
Premiums	1,022	1,122	2,081	2,219
Universal life and investment-type product policy fees	345	361	707	716
Net investment income	1,401	1,477	2,842	2,952
Other revenues	37	203	133	407
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	2,805	3,163	5,763	6,294
Expenses
Policyholder benefits and claims and policyholder dividends	1,720	1,927	3,456	3,750
Interest credited to policyholder account balances	255	261	512	519
Capitalization of DAC	(23)	(96)	(57)	(196)
Amortization of DAC and VOBA	139	269	213	417
Amortization of negative VOBA	0	0	0	0
Interest expense on debt	5	14	20	28
Other expenses	370	864	710	1,460
Total expenses	2,466	3,239	4,854	5,978
Provision for income tax expense (benefit)	104	(43)	289	82
Operating earnings	235	(33)	620	234
Operating Segments | Brighthouse Financial
Revenues
Premiums	217	280	394	673
Universal life and investment-type product policy fees	885	861	1,769	1,719
Net investment income	791	870	1,649	1,683
Other revenues	162	346	236	432
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	2,055	2,357	4,048	4,507
Expenses
Policyholder benefits and claims and policyholder dividends	654	1,008	1,285	1,711
Interest credited to policyholder account balances	283	291	558	580
Capitalization of DAC	(63)	(83)	(130)	(185)
Amortization of DAC and VOBA	136	152	336	314
Amortization of negative VOBA	0	0	0	0
Interest expense on debt	26	32	58	64
Other expenses	647	555	1,259	1,179
Total expenses	1,683	1,955	3,366	3,663
Provision for income tax expense (benefit)	89	105	155	220
Operating earnings	283	297	527	624
Operating Segments | Corporate & Other
Revenues
Premiums	10	13	47	11
Universal life and investment-type product policy fees	(32)	(31)	(63)	(56)
Net investment income	21	(35)	26	(30)
Other revenues	(68)	(301)	(110)	(352)
Net investment gains (losses)	0	0	0	0
Net derivative gains (losses)	0	0	0	0
Total revenues	(69)	(354)	(100)	(427)
Expenses
Policyholder benefits and claims and policyholder dividends	(15)	(10)	(6)	(36)
Interest credited to policyholder account balances	0	1	0	5
Capitalization of DAC	(3)	(3)	(4)	(7)
Amortization of DAC and VOBA	2	3	3	5
Amortization of negative VOBA	0	0	0	0
Interest expense on debt	257	254	503	518
Other expenses	61	(214)	151	(160)
Total expenses	302	31	647	325
Provision for income tax expense (benefit)	(271)	(188)	(554)	(371)
Operating earnings	(100)	(197)	(193)	(381)
Significant Reconciling Items
Revenues
Premiums	0	0	0	426
Universal life and investment-type product policy fees	111	113	212	306
Net investment income	75	6	276	(141)
Other revenues	5	3	11	3
Net investment gains (losses)	104	266	112	281
Net derivative gains (losses)	(437)	(2,099)	(1,363)	(764)
Total revenues	(142)	(1,711)	(752)	111
Expenses
Policyholder benefits and claims and policyholder dividends	272	213	620	613
Interest credited to policyholder account balances	213	186	615	211
Capitalization of DAC	0	0	0	(105)
Amortization of DAC and VOBA	(140)	(894)	(452)	(780)
Amortization of negative VOBA	(3)	(6)	(6)	(38)
Interest expense on debt	1	3	1	3
Other expenses	343	142	449	397
Total expenses	686	(356)	1,227	301
Provision for income tax expense (benefit)	$ (262)	$ (499)	$ (690)	$ (202)