Consolidated Supplementary Insurance Information (Balance Sheet Items) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	$ 19,627	$ 20,151	$ 19,653
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	212,545	216,142
Policyholder account balances	221,445	219,269
Policyholder Dividends Payable	385	386
Unearned Premiums	1,947	2,160
Unearned Revenue	4,635	4,537	4,106	$ 3,625
MRB (Assets) Liabilities (1)	2,209	2,893
Group Benefits
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	250	258
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	18,219	17,863
Policyholder account balances	7,632	7,692
Policyholder Dividends Payable	0	0
Unearned Premiums	593	446
Unearned Revenue	0	0
MRB (Assets) Liabilities (1)	0	0
RIS
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	565	413
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	73,356	71,223
Policyholder account balances	84,923	82,405
Policyholder Dividends Payable	0	0
Unearned Premiums	0	7
Unearned Revenue	27	31	36	38
MRB (Assets) Liabilities (1)	2	(13)
Asia
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	11,720	11,983
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	32,294	35,683
Policyholder account balances	94,903	92,063
Policyholder Dividends Payable	81	75
Unearned Premiums	1,175	1,532
Unearned Revenue	3,076	2,850	2,382	2,033
MRB (Assets) Liabilities (1)	215	234
Latin America
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	2,229	2,447
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	14,094	14,636
Policyholder account balances	5,514	6,368
Policyholder Dividends Payable	0	0
Unearned Premiums	2	2
Unearned Revenue	841	989	848	795
MRB (Assets) Liabilities (1)	0	0
EMEA
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	1,758	1,731
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	3,419	3,463
Policyholder account balances	7,214	7,578
Policyholder Dividends Payable	0	0
Unearned Premiums	22	18
Unearned Revenue	622	608	559	521
MRB (Assets) Liabilities (1)	(81)	(53)
MetLife Holdings
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	3,077	3,289
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	70,441	72,410
Policyholder account balances	21,274	23,178
Policyholder Dividends Payable	304	311
Unearned Premiums	155	155
Unearned Revenue	69	59	$ 281	$ 238
MRB (Assets) Liabilities (1)	2,069	2,722
Corporate And Other
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
DAC and VOBA	28	30
FPBs, Other Policy-Related Balances and Policyholder Dividend Obligation	722	864
Policyholder account balances	(15)	(15)
Policyholder Dividends Payable	0	0
Unearned Premiums	0	0
Unearned Revenue	0	0
MRB (Assets) Liabilities (1)	$ 4	$ 3