Market Risk Benefits - Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Market Risk Benefit [Line Items]
Beginning balance	$ 2,893
Effect of changes in capital markets	782	$ 658	$ 3,347
Ending balance	2,209	2,893
Asia
Market Risk Benefit [Line Items]
Beginning balance	234
Ending balance	215	234
MetLife Holdings
Market Risk Benefit [Line Items]
Beginning balance	2,722
Ending balance	2,069	2,722
Retirement Assurance | Asia
Market Risk Benefit [Line Items]
Beginning balance	203	226	277
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	205	233	284
Attributed fees collected	3	3	3
Benefit payments	(12)	(12)	0
Effect of changes in interest rates	4	1	(25)
Actual policyholder behavior different from expected behavior	(2)	(1)	6
Effect of changes in future expected policyholder behavior and other assumptions	0	(1)	5
Effect of foreign currency translation and other, net	(19)	(18)	(40)
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	179	205	233
Cumulative effect of changes in the instrument-specific credit risk	(1)	(2)	(8)
Effect of foreign currency translation on the cumulative instrument-specific credit risk	0	0	1
Ending balance	178	203	226
Retirement Assurance | Asia | At annuitization or exercise of other living benefits
Market Risk Benefit [Line Items]
Net amount at risk	$ 115	$ 119	$ 127
Average attained age of policyholders	58 years	58 years	58 years
Variable Annuity | MetLife Holdings
Market Risk Benefit [Line Items]
Beginning balance	$ 2,722	$ 3,225	$ 5,929
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	2,772	3,360	6,229
Attributed fees collected	352	377	387
Benefit payments	(90)	(58)	(42)
Effect of changes in interest rates	(736)	(161)	(3,610)
Effect of changes in capital markets	(514)	(900)	861
Effect of changes in equity index volatility	40	(135)	38
Actual policyholder behavior different from expected behavior	220	144	20
Effect of changes in future expected policyholder behavior and other assumptions	12	9	(328)
Effect of foreign currency translation and other, net	(4)	152	36
Effect of changes in risk margin	(60)	(16)	(231)
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	1,992	2,772	3,360
Cumulative effect of changes in the instrument-specific credit risk	78	(54)	(130)
Effect of foreign currency translation on the cumulative instrument-specific credit risk	(1)	4	(5)
Ending balance	2,069	2,722	3,225
Variable Annuity | MetLife Holdings | In the event of death
Market Risk Benefit [Line Items]
Net amount at risk	$ 2,543	$ 2,828	$ 4,387
Average attained age of policyholders	71 years	70 years	69 years
Variable Annuity | MetLife Holdings | At annuitization or exercise of other living benefits
Market Risk Benefit [Line Items]
Net amount at risk	$ 718	$ 675	$ 1,141
Average attained age of policyholders	70 years	70 years	71 years
Insurance, Other
Market Risk Benefit [Line Items]
Beginning balance	$ (32)	$ 32	$ 491
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	(50)	24	539
Attributed fees collected	49	34	61
Benefit payments	(6)	(28)	(4)
Effect of changes in interest rates	(57)	(3)	(499)
Effect of changes in capital markets	(3)	(41)	139
Effect of changes in equity index volatility	0	(6)	31
Actual policyholder behavior different from expected behavior	5	(22)	(12)
Effect of changes in future expected policyholder behavior and other assumptions	(2)	2	(1)
Effect of foreign currency translation and other, net	12	(9)	(224)
Effect of changes in risk margin	(1)	(1)	(6)
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	(53)	(50)	24
Cumulative effect of changes in the instrument-specific credit risk	16	17	7
Effect of foreign currency translation on the cumulative instrument-specific credit risk	(1)	1	1
Ending balance	(38)	(32)	32
Less: Reinsurance recoverable	12	18	23
Balance, end of period, net of reinsurance	$ (50)	$ (50)	$ 9