Future Policy Benefits - Disaggregate Rollforwards (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for FPBs	$ 190,993		$ 196,406
Fixed & Immediate Annuities | RIS
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period, at current discount rate at balance sheet date	0	$ 0
Balance, beginning of period, at original discount rate	0	0
Effect of actual variances from expected experience (1)	(25)	(29)
Adjusted balance	(25)	(29)
Issuances	4,206	2,558
Net premiums collected	(4,181)	(2,529)
Ending balance at original discount rate	0	0
Balance, end of period, at current discount rate at balance sheet date	0	0
Balance, beginning of period, at current discount rate at balance sheet date	64,515	58,695
Balance, beginning of period, at original discount rate	64,737	61,426
Effect of actual variances from expected experience (1)	(93)	(167)
Adjusted balance	64,644	61,259
Issuances	4,328	2,561
Interest accrual	1,526	1,411
Benefit payments	(2,976)	(2,726)
Ending balance at original discount rate	67,522	62,505
Effect of changes in discount rate assumptions	(2,847)	(2,020)
Balance, end of period, at current discount rate at balance sheet date	64,675	60,485
Cumulative amount of fair value hedging adjustments	(337)	(204)
Net liability for FPBs	64,338	60,281	64,324
Less: Reinsurance recoverables	1,933	0
Net liability for FPBs, net of reinsurance	62,405	60,281
Undiscounted - Expected future benefit payments	123,752	115,364
Discounted - Expected future benefit payments	$ 64,675	$ 60,485	64,515
Weighted-average duration of the liability	9 years	9 years
Weighted-average interest accretion (original locked-in) rate	4.70%	4.70%
Weighted-average current discount rate at balance sheet date	5.60%	5.30%
Deferred Profit Liability Offset to Actual Versus Expected	$ 49	$ 98
Whole and Term Life & Endowments | Asia
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period, at current discount rate at balance sheet date	4,561	4,682
Balance, beginning of period, at original discount rate	4,793	4,943
Effect of actual variances from expected experience (1)	(33)	(26)
Adjusted balance	4,760	4,917
Issuances	269	328
Interest accrual	34	27
Net premiums collected	(304)	(300)
Effect of foreign currency translation	(507)	(384)
Ending balance at original discount rate	4,252	4,588
Effect of changes in discount rate assumptions	(277)	(196)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	30	15
Balance, end of period, at current discount rate at balance sheet date	4,005	4,407
Balance, beginning of period, at current discount rate at balance sheet date	17,435	17,463
Balance, beginning of period, at original discount rate	17,198	18,209
Effect of actual variances from expected experience (1)	(33)	1
Adjusted balance	17,165	18,210
Issuances	269	328
Interest accrual	183	185
Benefit payments	(484)	(624)
Effect of foreign currency translation	(1,813)	(1,360)
Ending balance at original discount rate	15,320	16,739
Effect of changes in discount rate assumptions	(131)	154
Effect of foreign currency translation on the effect of changes in discount rate assumptions	76	11
Balance, end of period, at current discount rate at balance sheet date	15,265	16,904
Cumulative impact of flooring the future policyholder benefits reserve	0	2
Net liability for FPBs	11,260	12,499	12,874
Less: Reinsurance recoverables	(1)	(2)
Net liability for FPBs, net of reinsurance	11,261	12,501
Undiscounted - Expected future gross premiums	8,363	8,786
Undiscounted - Expected future benefit payments	25,574	26,771
Discounted - Expected future gross premiums	7,140	7,691
Discounted - Expected future benefit payments	$ 15,265	$ 16,904	17,435
Weighted-average duration of the liability	17 years	17 years
Weighted-average interest accretion (original locked-in) rate	2.60%	2.50%
Weighted-average current discount rate at balance sheet date	2.80%	2.50%
Accident & health insurance | Asia
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period, at current discount rate at balance sheet date	$ 19,835	$ 21,181
Balance, beginning of period, at original discount rate	21,232	22,594
Effect of actual variances from expected experience (1)	292	(33)
Adjusted balance	21,524	22,561
Issuances	551	536
Interest accrual	110	120
Net premiums collected	(928)	(1,055)
Effect of foreign currency translation	(2,496)	(1,849)
Ending balance at original discount rate	18,761	20,313
Effect of changes in discount rate assumptions	(1,720)	(1,006)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	187	83
Balance, end of period, at current discount rate at balance sheet date	17,228	19,390
Balance, beginning of period, at current discount rate at balance sheet date	30,480	30,879
Balance, beginning of period, at original discount rate	36,010	37,189
Effect of actual variances from expected experience (1)	331	(53)
Adjusted balance	36,341	37,136
Issuances	551	536
Interest accrual	232	246
Benefit payments	(614)	(653)
Effect of foreign currency translation	(4,161)	(3,017)
Ending balance at original discount rate	32,349	34,248
Effect of changes in discount rate assumptions	(6,761)	(4,664)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	750	385
Balance, end of period, at current discount rate at balance sheet date	26,338	29,969
Cumulative impact of flooring the future policyholder benefits reserve	79	83
Net liability for FPBs	9,189	10,662	10,712
Less: Reinsurance recoverables	143	149
Net liability for FPBs, net of reinsurance	9,046	10,513
Undiscounted - Expected future gross premiums	36,531	39,362
Undiscounted - Expected future benefit payments	42,531	44,435
Discounted - Expected future gross premiums	29,420	33,399
Discounted - Expected future benefit payments	$ 26,338	$ 29,969	30,480
Weighted-average duration of the liability	23 years	26 years
Weighted-average interest accretion (original locked-in) rate	1.70%	1.80%
Weighted-average current discount rate at balance sheet date	2.80%	2.30%
Deferred Profit Liability Offset to Actual Versus Expected	$ (6)
Fixed Annuity | Latin America
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period, at current discount rate at balance sheet date	0	$ 0
Balance, beginning of period, at original discount rate	0	0
Effect of actual variances from expected experience (1)	0	0
Adjusted balance	0	0
Issuances	494	525
Interest accrual	5	5
Net premiums collected	(499)	(530)
Ending balance at original discount rate	0	0
Balance, end of period, at current discount rate at balance sheet date	0	0
Balance, beginning of period, at current discount rate at balance sheet date	9,637	9,265
Balance, beginning of period, at original discount rate	9,249	8,240
Effect of actual variances from expected experience (1)	(9)	(9)
Adjusted balance	9,240	8,231
Issuances	509	577
Interest accrual	167	173
Benefit payments	(339)	(336)
Inflation adjustment	184	243
Effect of foreign currency translation	(691)	538
Ending balance at original discount rate	9,070	9,426
Effect of changes in discount rate assumptions	(28)	706
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(22)	60
Balance, end of period, at current discount rate at balance sheet date	9,020	10,192
Net liability for FPBs	9,020	10,192	9,637
Undiscounted - Expected future benefit payments	13,648	14,343
Discounted - Expected future benefit payments	$ 9,020	$ 10,192	9,637
Weighted-average duration of the liability	10 years	11 years
Weighted-average interest accretion (original locked-in) rate	3.60%	3.90%
Weighted-average current discount rate at balance sheet date	3.70%	2.90%
Deferred Profit Liability Offset to Actual Versus Expected		$ 3
Long-term Care | MetLife Holdings
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period, at current discount rate at balance sheet date	$ 5,687	5,775
Balance, beginning of period, at original discount rate	5,566	5,807
Effect of actual variances from expected experience (1)	13	83
Adjusted balance	5,579	5,890
Interest accrual	141	149
Net premiums collected	(286)	(293)
Ending balance at original discount rate	5,434	5,746
Effect of changes in discount rate assumptions	(80)	3
Balance, end of period, at current discount rate at balance sheet date	5,354	5,749
Balance, beginning of period, at current discount rate at balance sheet date	20,927	19,619
Balance, beginning of period, at original discount rate	20,494	20,165
Effect of actual variances from expected experience (1)	31	99
Adjusted balance	20,525	20,264
Interest accrual	540	534
Benefit payments	(421)	(382)
Ending balance at original discount rate	20,644	20,416
Effect of changes in discount rate assumptions	(835)	(169)
Balance, end of period, at current discount rate at balance sheet date	19,809	20,247
Net liability for FPBs	14,455	14,498	15,240
Undiscounted - Expected future gross premiums	10,280	10,893
Undiscounted - Expected future benefit payments	44,653	45,653
Discounted - Expected future gross premiums	6,715	7,089
Discounted - Expected future benefit payments	$ 19,809	$ 20,247	$ 20,927
Weighted-average duration of the liability	14 years	15 years
Weighted-average interest accretion (original locked-in) rate	5.40%	5.40%
Weighted-average current discount rate at balance sheet date	5.80%	5.50%