Disposition of MetLife Seguros S.A. (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net income (loss)	$ 1,589	$ 709	$ 3,775	$ 4,551	$ 5,364	$ 5,260
Disposal Group, Including Discontinued Operation, Assets	7,462	$ 0			7,462	$ 0
MetLife Seguros S.A [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net income (loss)	$ (205)				$ (205)
Disposal Group, Including Discontinued Operation, Assets							$ 201