Future Policy Benefits - Disaggregate Rollforwards (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Jan. 01, 2021
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Future Policy Benefit, before Reinsurance	$ 190,474		$ 187,222	$ 224,358
Variable Annuity [Member] | U.S.
Liability for Future Policy Benefit, by Product Segment [Line Items]
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)	(29)	(2)
Adjusted balance	(29)	(2)
Issuances	2,558	3,929
Net premiums collected	(2,529)	(3,927)
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	58,695	62,954
Balance, beginning of period, at original discount rate	61,426	50,890
Effect of actual variances from expected experience (1)	(167)	(79)
Adjusted balance	61,259	50,811
Issuances	2,561	3,933
Interest accrual	1,411	1,182
Benefit payments	(2,726)	(2,185)
Ending balance at original discount rate	62,505	53,741
Effect of changes in discount rate assumptions	(2,020)	797
Balance, end of period, at current discount rate at balance sheet date	60,485	54,538
Cumulative amount of fair value hedging adjustments	(204)	52
Liability for Future Policy Benefit, before Reinsurance	60,281	54,590	58,495
Less: Reinsurance recoverables	0	230
Liability for Future Policy Benefit, after Reinsurance	60,281	54,360
Undiscounted - Expected future benefit payments	115,364	101,128
Discounted - Expected future benefit payments (at current discount rate at balance sheet date)	$ 60,485	$ 54,538
Weighted-average duration of the liability	9 years	10 years
Weighted-average interest accretion (original locked-in) rate	4.70%	4.60%
Weighted-average current discount rate at balance sheet date	5.30%	4.80%
Deferred Profit Liability	$ 98	$ 53
Whole and Term Life & Endowments | Asia
Liability for Future Policy Benefit, by Product Segment [Line Items]
Balance, beginning of period, at current discount rate at balance sheet date	4,682	5,986
Balance, beginning of period, at original discount rate	4,943	5,881
Effect of actual variances from expected experience (1)	(26)	(17)
Adjusted balance	4,917	5,864
Issuances	328	106
Interest accrual	27	24
Net premiums collected	(300)	(323)
Effect of foreign currency translation	(384)	(826)
Ending balance at original discount rate	4,588	4,845
Effect of changes in discount rate assumptions	(196)	(90)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	15	(3)
Balance, end of period, at current discount rate at balance sheet date	4,407	4,752
Balance, beginning of period, at current discount rate at balance sheet date	17,463	24,453
Balance, beginning of period, at original discount rate	18,209	21,276
Effect of actual variances from expected experience (1)	1	9
Adjusted balance	18,210	21,285
Issuances	328	106
Interest accrual	185	191
Benefit payments	(624)	(787)
Effect of foreign currency translation	(1,360)	(2,901)
Ending balance at original discount rate	16,739	17,894
Effect of changes in discount rate assumptions	154	804
Effect of foreign currency translation on the effect of changes in discount rate assumptions	11	(180)
Balance, end of period, at current discount rate at balance sheet date	16,904	18,518
Cumulative amount of fair value hedging adjustments	2	19
Liability for Future Policy Benefit, before Reinsurance	12,499	13,785	12,792
Less: Reinsurance recoverables	(2)	(7)
Liability for Future Policy Benefit, after Reinsurance	12,501	13,792
Undiscounted - Expected future gross premiums	8,786	9,211
Undiscounted - Expected future benefit payments	26,771	27,795
Discounted - Expected future gross premiums	7,691	8,271
Discounted - Expected future benefit payments (at current discount rate at balance sheet date)	$ 16,904	$ 18,518
Weighted-average duration of the liability	17 years	16 years
Weighted-average interest accretion (original locked-in) rate	2.50%	2.40%
Weighted-average current discount rate at balance sheet date	2.50%	2.20%
Accident and Health Insurance Product Line | Asia
Liability for Future Policy Benefit, by Product Segment [Line Items]
Balance, beginning of period, at current discount rate at balance sheet date	$ 21,181	$ 26,543
Balance, beginning of period, at original discount rate	22,594	25,937
Effect of actual variances from expected experience (1)	(33)	26
Adjusted balance	22,561	25,963
Issuances	536	813
Interest accrual	120	132
Net premiums collected	(1,055)	(1,140)
Effect of foreign currency translation	(1,849)	(3,792)
Ending balance at original discount rate	20,313	21,976
Effect of changes in discount rate assumptions	(1,006)	(487)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	83	(2)
Balance, end of period, at current discount rate at balance sheet date	19,390	21,487
Balance, beginning of period, at current discount rate at balance sheet date	30,879	41,874
Balance, beginning of period, at original discount rate	37,189	41,517
Effect of actual variances from expected experience (1)	(53)	54
Adjusted balance	37,136	41,571
Issuances	536	814
Interest accrual	246	261
Benefit payments	(653)	(767)
Effect of foreign currency translation	(3,017)	(6,020)
Ending balance at original discount rate	34,248	35,859
Effect of changes in discount rate assumptions	(4,664)	(3,733)
Effect of foreign currency translation on the effect of changes in discount rate assumptions	385	276
Balance, end of period, at current discount rate at balance sheet date	29,969	32,402
Cumulative amount of fair value hedging adjustments	83	193
Liability for Future Policy Benefit, before Reinsurance	10,662	11,108	10,040
Less: Reinsurance recoverables	149	(11)
Liability for Future Policy Benefit, after Reinsurance	10,513	11,119
Undiscounted - Expected future gross premiums	39,362	42,467
Undiscounted - Expected future benefit payments	44,435	46,153
Discounted - Expected future gross premiums	33,399	37,169
Discounted - Expected future benefit payments (at current discount rate at balance sheet date)	$ 29,969	$ 32,402
Weighted-average duration of the liability	26 years	26 years
Weighted-average interest accretion (original locked-in) rate	1.80%	1.80%
Weighted-average current discount rate at balance sheet date	2.30%	2.10%
Fixed Annuity | Latin America
Liability for Future Policy Benefit, by Product Segment [Line Items]
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	1
Adjusted balance	0	1
Issuances	525	352
Interest accrual	5	(1)
Net premiums collected	(530)	(352)
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	9,265	7,343
Balance, beginning of period, at original discount rate	8,240	6,851
Effect of actual variances from expected experience (1)	(9)	(33)
Adjusted balance	8,231	6,818
Issuances	577	376
Interest accrual	173	145
Benefit payments	(336)	(291)
Inflation adjustment	243	469
Effect of foreign currency translation	538	(663)
Ending balance at original discount rate	9,426	6,854
Effect of changes in discount rate assumptions	706	916
Effect of foreign currency translation on the effect of changes in discount rate assumptions	60	(95)
Balance, end of period, at current discount rate at balance sheet date	10,192	7,675
Liability for Future Policy Benefit, before Reinsurance	10,192	7,675	9,265
Undiscounted - Expected future benefit payments	14,343	10,626
Discounted - Expected future benefit payments (at current discount rate at balance sheet date)	$ 10,192	$ 7,675
Weighted-average duration of the liability	11 years	11 years
Weighted-average interest accretion (original locked-in) rate	3.90%	4.40%
Weighted-average current discount rate at balance sheet date	2.90%	2.70%
Deferred Profit Liability	$ 3	$ 18
Long-term Care | MetLife Holdings
Liability for Future Policy Benefit, by Product Segment [Line Items]
Balance, beginning of period, at current discount rate at balance sheet date	5,775	7,058
Balance, beginning of period, at original discount rate	5,807	5,699
Effect of actual variances from expected experience (1)	83	106
Adjusted balance	5,890	5,805
Interest accrual	149	147
Net premiums collected	(293)	(288)
Ending balance at original discount rate	5,746	5,664
Effect of changes in discount rate assumptions	3	288
Balance, end of period, at current discount rate at balance sheet date	5,749	5,952
Balance, beginning of period, at current discount rate at balance sheet date	19,619	27,627
Balance, beginning of period, at original discount rate	20,165	19,406
Effect of actual variances from expected experience (1)	99	116
Adjusted balance	20,264	19,522
Interest accrual	534	515
Benefit payments	(382)	(345)
Ending balance at original discount rate	20,416	19,692
Effect of changes in discount rate assumptions	(169)	1,088
Balance, end of period, at current discount rate at balance sheet date	20,247	20,780
Liability for Future Policy Benefit, before Reinsurance	14,498	14,828	$ 13,845
Undiscounted - Expected future gross premiums	10,893	11,062
Undiscounted - Expected future benefit payments	45,653	45,787
Discounted - Expected future gross premiums	7,089	7,501
Discounted - Expected future benefit payments (at current discount rate at balance sheet date)	$ 20,247	$ 20,780
Weighted-average duration of the liability	15 years	16 years
Weighted-average interest accretion (original locked-in) rate	5.40%	5.50%
Weighted-average current discount rate at balance sheet date	5.50%	5.00%