Policyholder Account Balances - LDTI Rollforward (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	$ 219,269
Balance, end of period	219,543
Group Life - Term | Group Benefits
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	7,692	$ 8,028
Deposits	1,959	1,685
Policy charges	(327)	(318)
Surrenders and withdrawals	(1,767)	(1,608)
Benefit payments	(6)	(6)
Net transfers from (to) separate accounts	(3)	1
Interest credited	96	93
Balance, end of period	$ 7,644	$ 7,875
Weighted-average annual crediting rate	2.50%	2.40%
Cash surrender value	$ 7,584	$ 7,813
Group Life - Term | In the event of death | Group Benefits
Policyholder Account Balance [Roll Forward]
Net amount at risk	264,497	251,590
Capital Markets Investment Products and Stable Value GICs | RIS
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	64,140	63,723
Deposits	37,608	38,526
Surrenders and withdrawals	(37,540)	(39,865)
Interest credited	1,180	971
Effect of foreign currency translation and other, net	(443)	748
Balance, end of period	$ 64,945	$ 64,103
Weighted-average annual crediting rate	3.70%	3.10%
Cash surrender value	$ 1,850	$ 2,309
Annuities and Risk Solutions | RIS
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	17,711	15,549
Deposits	1,467	1,362
Policy charges	(63)	(96)
Surrenders and withdrawals	(189)	(83)
Benefit payments	(471)	(385)
Net transfers from (to) separate accounts	20	54
Interest credited	360	307
Other	(38)	(15)
Balance, end of period	$ 18,797	$ 16,693
Weighted-average annual crediting rate	4.00%	3.80%
Cash surrender value	$ 8,209	$ 7,683
Annuities and Risk Solutions | In the event of death | RIS
Policyholder Account Balance [Roll Forward]
Net amount at risk	43,702	43,311
Universal and Variable Universal Life | Asia
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	49,739	46,417
Deposits	3,146	3,244
Policy charges	(545)	(563)
Surrenders and withdrawals	(1,736)	(1,238)
Benefit payments	(234)	(287)
Interest credited	744	683
Effect of foreign currency translation and other, net	(1,885)	(1,405)
Balance, end of period	$ 49,229	$ 46,851
Weighted-average annual crediting rate	3.10%	3.00%
Cash surrender value	$ 43,078	$ 40,257
Universal and Variable Universal Life | In the event of death | Asia
Policyholder Account Balance [Roll Forward]
Net amount at risk	88,255	92,521
Fixed Annuity | Asia
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	36,863	32,454
Deposits	3,412	4,612
Policy charges	(1)	(1)
Surrenders and withdrawals	(1,645)	(1,003)
Benefit payments	(1,174)	(1,071)
Interest credited	509	404
Effect of foreign currency translation and other, net	(335)	(271)
Balance, end of period	$ 37,629	$ 35,124
Weighted-average annual crediting rate	2.80%	2.40%
Cash surrender value	$ 32,555	$ 30,244
Fixed Annuity | MetLife Holdings
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	11,537	13,286
Deposits	86	132
Policy charges	(7)	(8)
Surrenders and withdrawals	(903)	(1,038)
Benefit payments	(211)	(224)
Net transfers from (to) separate accounts	58	47
Interest credited	183	200
Other	4	15
Balance, end of period	$ 10,747	$ 12,410
Weighted-average annual crediting rate	3.40%	3.20%
Cash surrender value	$ 10,154	$ 11,629
Fixed Annuity | In the event of death | Asia
Policyholder Account Balance [Roll Forward]
Net amount at risk	0	6,224
Fixed Annuity | In the event of death | MetLife Holdings
Policyholder Account Balance [Roll Forward]
Net amount at risk	2,541	3,246
Fixed Annuity | At annuitization or exercise of other living benefits | MetLife Holdings
Policyholder Account Balance [Roll Forward]
Net amount at risk	707	813
Variable Annuity | EMEA
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	2,720	2,802
Deposits	2	2
Policy charges	(30)	(32)
Surrenders and withdrawals	(142)	(132)
Benefit payments	(61)	(64)
Interest credited	87	32
Effect of foreign currency translation and other, net	(24)	153
Balance, end of period	$ 2,552	$ 2,761
Weighted-average annual crediting rate	6.80%	2.40%
Cash surrender value	$ 2,552	$ 2,761
Variable Annuity | In the event of death | EMEA
Policyholder Account Balance [Roll Forward]
Net amount at risk	410	635
Variable Annuity | At annuitization or exercise of other living benefits | EMEA
Policyholder Account Balance [Roll Forward]
Net amount at risk	529	797
Life and Other | MetLife Holdings
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	11,641	12,402
Deposits	381	446
Policy charges	(347)	(354)
Surrenders and withdrawals	(523)	(612)
Benefit payments	(76)	(85)
Net transfers from (to) separate accounts	19	21
Interest credited	211	223
Other	(3)	3
Balance, end of period	$ 11,303	$ 12,044
Weighted-average annual crediting rate	3.70%	3.70%
Cash surrender value	$ 10,863	$ 11,556
Net amount at risk percentage after taking reinsurance into consideration	99.00%		99.00%
Life and Other | In the event of death | MetLife Holdings
Policyholder Account Balance [Roll Forward]
Net amount at risk	$ 65,885	$ 69,633