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Market Risk Benefits Balance Sheet (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Market Risk Benefit [Line Items]
Asset	$ 351	$ 286
Liability	2,696	3,179
Net	2,345	2,893
Retirement Assurance \| Asia
Market Risk Benefit [Line Items]
Asset	0	0
Liability	189	203
Net	189	203	$ 221	$ 226
Investment Product \| MetLife Holdings
Market Risk Benefit [Line Items]
Asset	206	156
Liability	2,437	2,878
Net	2,231	2,722
Insurance, Other
Market Risk Benefit [Line Items]
Asset	145	130
Liability	70	98
Net	$ (75)	$ (32)	$ 60	$ 32