Policyholder Account Balances - Amounts on Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Policyholder Account Balance [Line Items]
Policyholder account balance	$ 219,543	$ 219,269
Other Products
Policyholder Account Balance [Line Items]
Policyholder account balance	16,697	17,226
Group Life - Term | Group Benefits
Policyholder Account Balance [Line Items]
Policyholder account balance	7,644	7,692	$ 7,875	$ 8,028
Capital Markets Investment Products and Stable Value GICs | RIS
Policyholder Account Balance [Line Items]
Policyholder account balance	64,945	64,140	64,103	63,723
Annuities and Risk Solutions | RIS
Policyholder Account Balance [Line Items]
Policyholder account balance	18,797	17,711	16,693	15,549
Universal and Variable Universal Life | Asia
Policyholder Account Balance [Line Items]
Policyholder account balance	49,229	49,739	46,851	46,417
Fixed Annuity | Asia
Policyholder Account Balance [Line Items]
Policyholder account balance	37,629	36,863	35,124	32,454
Fixed Annuity | MetLife Holdings
Policyholder Account Balance [Line Items]
Policyholder account balance	10,747	11,537	12,410	13,286
Variable Annuity | EMEA
Policyholder Account Balance [Line Items]
Policyholder account balance	2,552	2,720	2,761	2,802
Life and Other | MetLife Holdings
Policyholder Account Balance [Line Items]
Policyholder account balance	$ 11,303	$ 11,641	$ 12,044	$ 12,402