Deferred Policy Acquisition Costs, Value of Business Acquired and Other Policy-Related Intangibles (DAC and VOBA by Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
DAC and VOBA	$ 16,061	$ 16,389	$ 17,833
U.S.
Segment Reporting Information [Line Items]
DAC and VOBA	440	434
Asia
Segment Reporting Information [Line Items]
DAC and VOBA	9,339	9,333
Latin America
Segment Reporting Information [Line Items]
DAC and VOBA	2,021	2,092
EMEA
Segment Reporting Information [Line Items]
DAC and VOBA	1,623	1,787
MetLife Holdings
Segment Reporting Information [Line Items]
DAC and VOBA	2,607	2,712
Corporate & Other
Segment Reporting Information [Line Items]
DAC and VOBA	$ 31	$ 31