Deferred Policy Acquisition Costs, Value of Business Acquired and Other Policy-Related Intangibles (DAC and VOBA by Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2021
Segment Reporting Information [Line Items]
DAC and VOBA	$ 20,151	$ 19,653	$ 19,806	$ 20,417
Group Benefits
Segment Reporting Information [Line Items]
DAC and VOBA	258	264
Retirement and Income Solutions
Segment Reporting Information [Line Items]
DAC and VOBA	413	286
Asia
Segment Reporting Information [Line Items]
DAC and VOBA	11,983	11,560
Latin America
Segment Reporting Information [Line Items]
DAC and VOBA	2,447	2,087
EMEA
Segment Reporting Information [Line Items]
DAC and VOBA	1,731	1,607
MetLife Holdings
Segment Reporting Information [Line Items]
DAC and VOBA	3,289	3,819
Corporate & Other
Segment Reporting Information [Line Items]
DAC and VOBA	$ 30	$ 30