Market Risk Benefits Rollforward (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Market Risk Benefit [Line Items]
Beginning balance	$ 2,893
Ending balance	2,807
Retirement Assurance | Asia
Market Risk Benefit [Line Items]
Beginning balance	203	$ 226
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	205	233
Attributed fees collected	3	2
Benefit payments	(9)	(9)
Effect of changes in interest rates	4	2
Actual policyholder behavior different from expected behavior	(2)	(1)
Effect of changes in future expected policyholder behavior and other assumptions	0	(1)
Effect of foreign currency translation and other, net	(3)	(30)
Balance, end of period, before the cumulative effect of changes in the instrument-specific credit risk	198	196
Cumulative effect of changes in the instrument-specific credit risk	(1)	(3)
Ending balance	197	193
Retirement Assurance | Asia | At annuitization or exercise of other living benefits
Market Risk Benefit [Line Items]
Net amount at risk	$ 122	$ 116
Average attained age of policyholders	58 years	58 years
Variable Annuity | MetLife Holdings
Market Risk Benefit [Line Items]
Beginning balance	$ 2,722	$ 3,225
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	2,772	3,360
Attributed fees collected	266	286
Benefit payments	(67)	(36)
Effect of changes in interest rates	(70)	(881)
Effect of changes in capital markets	(527)	(542)
Effect of changes in equity index volatility	37	(84)
Actual policyholder behavior different from expected behavior	176	95
Effect of changes in future expected policyholder behavior and other assumptions	12	9
Effect of foreign currency translation and other, net	34	118
Effect of changes in risk margin	(7)	(46)
Balance, end of period, before the cumulative effect of changes in the instrument-specific credit risk	2,626	2,279
Cumulative effect of changes in the instrument-specific credit risk	(19)	(16)
Effect of foreign currency translation on the cumulative instrument-specific credit risk	1	5
Ending balance	2,608	2,268
Variable Annuity | MetLife Holdings | In the event of death
Market Risk Benefit [Line Items]
Net amount at risk	$ 2,243	$ 3,979
Average attained age of policyholders	71 years	70 years
Variable Annuity | MetLife Holdings | At annuitization or exercise of other living benefits
Market Risk Benefit [Line Items]
Net amount at risk	$ 643	$ 921
Average attained age of policyholders	68 years	70 years
Insurance, Other
Market Risk Benefit [Line Items]
Beginning balance	$ (32)	$ 32
Balance, beginning of period, before effect of cumulative changes in the instrument-specific credit risk	(50)	24
Attributed fees collected	38	23
Benefit payments	(5)	(23)
Effect of changes in interest rates	(12)	(98)
Effect of changes in capital markets	(8)	(15)
Effect of changes in equity index volatility	0	(4)
Actual policyholder behavior different from expected behavior	6	(21)
Effect of changes in future expected policyholder behavior and other assumptions	(2)	2
Effect of foreign currency translation and other, net	22	37
Effect of changes in risk margin	(1)	(2)
Balance, end of period, before the cumulative effect of changes in the instrument-specific credit risk	(12)	(77)
Cumulative effect of changes in the instrument-specific credit risk	13	20
Effect of foreign currency translation on the cumulative instrument-specific credit risk	1	0
Ending balance	2	(57)
Less: Reinsurance recoverable	16	18
Balance, end of period, net of reinsurance	$ (14)	$ (75)