Future Policy Benefits - Disaggregate Rollforwards (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for FPBs	$ 198,965		$ 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)	(39)	(25)
Adjusted balance	(39)	(25)
Issuances	2,769	4,206
Net premiums collected	(2,730)	(4,181)
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)	(100)	(93)
Adjusted balance	69,543	64,644
Issuances	2,797	4,328
Interest accrual	1,676	1,526
Benefit payments	(3,288)	(2,976)
Effect of foreign currency translation	27	0
Ending balance at original discount rate	70,755	67,522
Effect of changes in discount rate assumptions	(2,280)	(2,847)
Balance, end of period, at current discount rate at balance sheet date	68,475	64,675
Cumulative amount of fair value hedging adjustments	(282)	(337)
Net liability for FPBs	68,193	64,338	66,262
Less: Reinsurance recoverables	2,207	1,933
Net liability for FPBs, net of reinsurance	65,986	62,405
Undiscounted - Expected future benefit payments	128,551	123,752
Discounted - Expected future benefit payments	$ 68,475	$ 64,675	66,621
Weighted-average duration of the liability	8 years	9 years
Weighted-average interest accretion (original locked-in) rate	4.90%	4.70%
Weighted-average current discount rate at balance sheet date	5.50%	5.60%
Deferred Profit Liability Offset to Actual Versus Expected	$ 46	$ 49
Fixed & Immediate Annuities | Asia
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Deferred Profit Liability Offset to Actual Versus Expected		(6)
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)	(44)	(33)
Adjusted balance	4,242	4,760
Issuances	290	269
Interest accrual	39	34
Net premiums collected	(313)	(304)
Effect of foreign currency translation	340	(507)
Ending balance at original discount rate	4,598	4,252
Effect of changes in discount rate assumptions	(332)	(277)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(25)	30
Balance, end of period, at current discount rate at balance sheet date	4,241	4,005
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)	(43)	(33)
Adjusted balance	15,209	17,165
Issuances	290	269
Interest accrual	188	183
Benefit payments	(482)	(484)
Effect of foreign currency translation	1,286	(1,813)
Ending balance at original discount rate	16,491	15,320
Effect of changes in discount rate assumptions	(433)	(131)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	27	76
Balance, end of period, at current discount rate at balance sheet date	16,085	15,265
Net liability for FPBs	11,844	11,260	11,167
Less: Reinsurance recoverables	(2)	(1)
Net liability for FPBs, net of reinsurance	11,846	11,261
Undiscounted - Expected future gross premiums	9,474	8,363
Undiscounted - Expected future benefit payments	27,843	25,574
Discounted - Expected future gross premiums	7,837	7,140
Discounted - Expected future benefit payments	$ 16,085	$ 15,265	15,190
Weighted-average duration of the liability	17 years	17 years
Weighted-average interest accretion (original locked-in) rate	2.60%	2.60%
Weighted-average current discount rate at balance sheet date	3.00%	2.80%
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)	(200)	292
Adjusted balance	18,620	21,524
Issuances	636	551
Interest accrual	113	110
Net premiums collected	(939)	(928)
Effect of foreign currency translation	1,836	(2,496)
Ending balance at original discount rate	20,266	18,761
Effect of changes in discount rate assumptions	(2,204)	(1,720)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(161)	187
Balance, end of period, at current discount rate at balance sheet date	17,901	17,228
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)	(208)	331
Adjusted balance	32,630	36,341
Issuances	635	551
Interest accrual	239	232
Benefit payments	(647)	(614)
Effect of foreign currency translation	3,064	(4,161)
Ending balance at original discount rate	35,921	32,349
Effect of changes in discount rate assumptions	(8,209)	(6,761)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	(572)	750
Balance, end of period, at current discount rate at balance sheet date	27,140	26,338
Cumulative impact of flooring the future policyholder benefits reserve	156	79
Net liability for FPBs	9,395	9,189	9,406
Less: Reinsurance recoverables	132	143
Net liability for FPBs, net of reinsurance	9,263	9,046
Undiscounted - Expected future gross premiums	40,090	36,531
Undiscounted - Expected future benefit payments	47,275	42,531
Discounted - Expected future gross premiums	30,717	29,420
Discounted - Expected future benefit payments	$ 27,140	$ 26,338	26,565
Weighted-average duration of the liability	21 years	23 years
Weighted-average interest accretion (original locked-in) rate	1.70%	1.70%
Weighted-average current discount rate at balance sheet date	3.20%	2.80%
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	740	494
Interest accrual	2	5
Net premiums collected	(742)	(499)
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)	(1)	(9)
Adjusted balance	9,132	9,240
Issuances	778	509
Interest accrual	181	167
Benefit payments	(389)	(339)
Inflation adjustment	216	184
Effect of foreign currency translation	621	(691)
Ending balance at original discount rate	10,539	9,070
Effect of changes in discount rate assumptions	397	(28)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	28	(22)
Balance, end of period, at current discount rate at balance sheet date	10,964	9,020
Net liability for FPBs	10,964	9,020	9,600
Undiscounted - Expected future benefit payments	15,671	13,648
Discounted - Expected future benefit payments	$ 10,964	$ 9,020	9,600
Weighted-average duration of the liability	10 years	10 years
Weighted-average interest accretion (original locked-in) rate	3.70%	3.60%
Weighted-average current discount rate at balance sheet date	3.10%	3.70%
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)	(3)	13
Adjusted balance	5,565	5,579
Interest accrual	141	141
Net premiums collected	(280)	(286)
Ending balance at original discount rate	5,426	5,434
Effect of changes in discount rate assumptions	(6)	(80)
Balance, end of period, at current discount rate at balance sheet date	5,420	5,354
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)	26	31
Adjusted balance	21,050	20,525
Interest accrual	553	540
Benefit payments	(452)	(421)
Ending balance at original discount rate	21,151	20,644
Effect of changes in discount rate assumptions	(928)	(835)
Balance, end of period, at current discount rate at balance sheet date	20,223	19,809
Net liability for FPBs	14,803	14,455	14,537
Undiscounted - Expected future gross premiums	10,269	10,280
Undiscounted - Expected future benefit payments	44,566	44,653
Discounted - Expected future gross premiums	6,870	6,715
Discounted - Expected future benefit payments	$ 20,223	$ 19,809	$ 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%	5.80%