Future Policy Benefits - Disaggregate Rollforwards (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for FPBs	$ 197,667		$ 193,646
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)	(32)	(26)
Adjusted balance	(32)	(26)
Issuances	2,150	342
Net premiums collected	(2,118)	(316)
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	66,621	64,515
Balance, beginning of period, at original discount rate	69,643	64,737
Effect of actual variances from expected experience (1)	(80)	(36)
Adjusted balance	69,563	64,701
Issuances	2,179	341
Interest accrual	833	759
Benefit payments	(1,620)	(1,492)
Effect of foreign currency translation	9	0
Ending balance at original discount rate	70,964	64,309
Effect of changes in discount rate assumptions	(2,533)	(1,649)
Balance, end of period, at current discount rate at balance sheet date	68,431	62,660
Cumulative amount of fair value hedging adjustments	(285)	(298)
Net liability for FPBs	68,146	62,362	66,262
Less: Reinsurance recoverables	2,228	256
Net liability for FPBs, net of reinsurance	65,918	62,106
Undiscounted - Expected future benefit payments	128,949	118,190
Discounted - Expected future benefit payments	$ 68,431	$ 62,660	66,621
Weighted-average duration of the liability	8 years	9 years
Weighted-average interest accretion (original locked-in) rate	4.90%	4.80%
Weighted-average current discount rate at balance sheet date	5.50%	5.40%
Deferred Profit Liability Offset to Actual Versus Expected	$ 34	$ 10
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	4,023	4,561
Balance, beginning of period, at original discount rate	4,286	4,793
Effect of actual variances from expected experience (1)	(14)	(15)
Adjusted balance	4,272	4,778
Issuances	149	153
Interest accrual	19	17
Net premiums collected	(155)	(157)
Effect of foreign currency translation	155	(290)
Ending balance at original discount rate	4,440	4,501
Effect of changes in discount rate assumptions	(318)	(260)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(14)	16
Balance, end of period, at current discount rate at balance sheet date	4,108	4,257
Balance, beginning of period, at current discount rate at balance sheet date	15,190	17,435
Balance, beginning of period, at original discount rate	15,252	17,198
Effect of actual variances from expected experience (1)	(12)	(7)
Adjusted balance	15,240	17,191
Issuances	149	153
Interest accrual	91	93
Benefit payments	(244)	(263)
Effect of foreign currency translation	544	(1,042)
Ending balance at original discount rate	15,780	16,132
Effect of changes in discount rate assumptions	(22)	(36)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(85)	22
Balance, end of period, at current discount rate at balance sheet date	15,673	16,118
Net liability for FPBs	11,565	11,861	11,167
Less: Reinsurance recoverables	(2)	(1)
Net liability for FPBs, net of reinsurance	11,567	11,862
Undiscounted - Expected future gross premiums	9,043	8,799
Undiscounted - Expected future benefit payments	26,263	26,638
Discounted - Expected future gross premiums	7,512	7,549
Discounted - Expected future benefit payments	$ 15,673	$ 16,118	15,190
Weighted-average duration of the liability	18 years	17 years
Weighted-average interest accretion (original locked-in) rate	2.60%	2.60%
Weighted-average current discount rate at balance sheet date	2.80%	2.70%
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	$ 17,203	$ 19,835
Balance, beginning of period, at original discount rate	18,820	21,232
Effect of actual variances from expected experience (1)	(125)	(123)
Adjusted balance	18,695	21,109
Issuances	338	252
Interest accrual	55	56
Net premiums collected	(470)	(483)
Effect of foreign currency translation	1,072	(1,399)
Ending balance at original discount rate	19,690	19,535
Effect of changes in discount rate assumptions	(2,017)	(1,549)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(84)	99
Balance, end of period, at current discount rate at balance sheet date	17,589	18,085
Balance, beginning of period, at current discount rate at balance sheet date	26,565	30,480
Balance, beginning of period, at original discount rate	32,838	36,010
Effect of actual variances from expected experience (1)	(132)	(130)
Adjusted balance	32,706	35,880
Issuances	337	252
Interest accrual	116	118
Benefit payments	(310)	(303)
Effect of foreign currency translation	1,661	(2,334)
Ending balance at original discount rate	34,510	33,613
Effect of changes in discount rate assumptions	(6,967)	(6,132)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(325)	395
Balance, end of period, at current discount rate at balance sheet date	27,218	27,876
Cumulative impact of flooring the future policyholder benefits reserve	50	68
Net liability for FPBs	9,679	9,859	9,406
Less: Reinsurance recoverables	141	166
Net liability for FPBs, net of reinsurance	9,538	9,693
Undiscounted - Expected future gross premiums	38,785	38,523
Undiscounted - Expected future benefit payments	45,242	43,983
Discounted - Expected future gross premiums	30,160	31,377
Discounted - Expected future benefit payments	$ 27,218	$ 27,876	26,565
Weighted-average duration of the liability	23 years	24 years
Weighted-average interest accretion (original locked-in) rate	1.70%	1.70%
Weighted-average current discount rate at balance sheet date	2.90%	2.70%
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	330	260
Interest accrual	1	1
Net premiums collected	(331)	(261)
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	9,600	9,637
Balance, beginning of period, at original discount rate	9,133	9,249
Effect of actual variances from expected experience (1)	(2)	(5)
Adjusted balance	9,131	9,244
Issuances	348	265
Interest accrual	88	82
Benefit payments	(188)	(165)
Inflation adjustment	120	73
Effect of foreign currency translation	400	(976)
Ending balance at original discount rate	9,899	8,523
Effect of changes in discount rate assumptions	468	285
Effect of foreign currency translation on the effect of changes in discount rate assumptions	21	(37)
Balance, end of period, at current discount rate at balance sheet date	10,388	8,771
Net liability for FPBs	10,388	8,771	9,600
Undiscounted - Expected future benefit payments	14,760	12,863
Discounted - Expected future benefit payments	$ 10,388	$ 8,771	9,600
Weighted-average duration of the liability	11 years	10 years
Weighted-average interest accretion (original locked-in) rate	3.70%	3.70%
Weighted-average current discount rate at balance sheet date	3.10%	3.40%
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	$ 5,475	$ 5,687
Balance, beginning of period, at original discount rate	5,568	5,566
Effect of actual variances from expected experience (1)	(22)	(4)
Adjusted balance	5,546	5,562
Interest accrual	71	71
Net premiums collected	(140)	(143)
Ending balance at original discount rate	5,477	5,490
Effect of changes in discount rate assumptions	(35)	0
Balance, end of period, at current discount rate at balance sheet date	5,442	5,490
Balance, beginning of period, at current discount rate at balance sheet date	20,012	20,927
Balance, beginning of period, at original discount rate	21,024	20,494
Effect of actual variances from expected experience (1)	(10)	(1)
Adjusted balance	21,014	20,493
Interest accrual	276	269
Benefit payments	(225)	(212)
Ending balance at original discount rate	21,065	20,550
Effect of changes in discount rate assumptions	(907)	(215)
Balance, end of period, at current discount rate at balance sheet date	20,158	20,335
Net liability for FPBs	14,716	14,845	14,537
Undiscounted - Expected future gross premiums	10,450	10,430
Undiscounted - Expected future benefit payments	44,745	44,808
Discounted - Expected future gross premiums	6,932	6,895
Discounted - Expected future benefit payments	$ 20,158	$ 20,335	$ 20,012
Weighted-average duration of the liability	13 years	14 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%