Market Risk Benefits Rollforward (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Market Risk Benefit [Line Items]
Beginning balance	$ 2,893
Ending balance	2,345
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	1	1
Benefit payments	(2)	0
Effect of changes in interest rates	2	7
Actual policyholder behavior different from expected behavior	(1)	(7)
Effect of foreign currency translation and other, net	(15)	(8)
Balance, end of period, before the cumulative effect of changes in the instrument-specific credit risk	190	226
Cumulative effect of changes in the instrument-specific credit risk	(1)	(5)
Ending balance	189	221
Retirement Assurance | Asia | At annuitization or exercise of other living benefits
Market Risk Benefit [Line Items]
Net amount at risk	$ 113	$ 121
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	90	98
Benefit payments	(22)	(11)
Effect of changes in interest rates	(373)	368
Effect of changes in capital markets	(306)	(358)
Effect of changes in equity index volatility	34	(132)
Actual policyholder behavior different from expected behavior	69	29
Effect of foreign currency translation and other, net	(26)	232
Effect of changes in risk margin	(46)	3
Balance, end of period, before the cumulative effect of changes in the instrument-specific credit risk	2,192	3,589
Cumulative effect of changes in the instrument-specific credit risk	39	(229)
Effect of foreign currency translation on the cumulative instrument-specific credit risk	0	1
Ending balance	2,231	3,361
Variable Annuity | MetLife Holdings | In the event of death
Market Risk Benefit [Line Items]
Net amount at risk	$ 2,489	$ 3,619
Average attained age of policyholders	72 years	70 years
Variable Annuity | MetLife Holdings | At annuitization or exercise of other living benefits
Market Risk Benefit [Line Items]
Net amount at risk	$ 579	$ 897
Average attained age of policyholders	70 years	71 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	13	8
Benefit payments	(2)	(15)
Effect of changes in interest rates	(42)	61
Effect of changes in capital markets	(13)	(24)
Effect of changes in equity index volatility	(1)	(4)
Actual policyholder behavior different from expected behavior	2	(21)
Effect of foreign currency translation and other, net	(4)	34
Effect of changes in risk margin	(1)	0
Balance, end of period, before the cumulative effect of changes in the instrument-specific credit risk	(98)	63
Cumulative effect of changes in the instrument-specific credit risk	23	(3)
Ending balance	(75)	60
Less: Reinsurance recoverable	13	25
Balance, end of period, net of reinsurance	$ (88)	$ 35