Future Policy Benefits - FPB Income Statement (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	$ 5,076	$ 3,208
Interest Expense (2)	1,485	1,397
Fixed & Immediate Annuities | RIS
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	2,150	344
Interest Expense (2)	833	759
Whole and Term Life & Endowments | Asia
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	294	290
Interest Expense (2)	72	76
Accident & health insurance | Asia
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	778	811
Interest Expense (2)	61	62
Fixed Annuity | Latin America
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	331	261
Interest Expense (2)	87	81
Long-term Care | MetLife Holdings
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	180	181
Interest Expense (2)	205	198
Fixed & Immediate Annuities for Deferred Profit Liabilities | RIS
Principal Transaction Revenue [Line Items]
Interest Expense (2)	46	44
Whole and Term Life & Endowments for Deferred Profit Liabilities | Asia
Principal Transaction Revenue [Line Items]
Interest Expense (2)	10	9
Accident and Health Insurance Product Line for Deferred Profit Liabilities | Asia
Principal Transaction Revenue [Line Items]
Interest Expense (2)	5	5
Fixed Annuity for Deferred Profit Liabilities | Latin America
Principal Transaction Revenue [Line Items]
Interest Expense (2)	5	5
Variable Life | Asia
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	32	29
Interest Expense (2)	4	4
Universal and Variable Universal Life | Asia
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	0	(33)
Interest Expense (2)	1	1
Universal and Variable Universal Life | MetLife Holdings
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	159	167
Interest Expense (2)	34	32
Long-Duration Insurance, Other
Principal Transaction Revenue [Line Items]
Gross Premiums or Assessments (1)	1,152	1,158
Interest Expense (2)	$ 122	$ 121