Market Risk Benefits Balance Sheet (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Market Risk Benefit [Line Items]
Asset	$ 310	$ 286
Liability	3,117	3,179
Net	2,807	2,893
Retirement Assurance | Asia
Market Risk Benefit [Line Items]
Asset	0	0
Liability	197	203
Net	197	203	$ 193	$ 226
Investment Product | MetLife Holdings
Market Risk Benefit [Line Items]
Asset	179	156
Liability	2,787	2,878
Net	2,608	2,722
Insurance, Other
Market Risk Benefit [Line Items]
Asset	131	130
Liability	133	98
Net	$ 2	$ (32)	$ (57)	$ 32