Segment Information (Total Assets) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Separate account assets	$ 179,873	$ 199,970
Separate account liabilities	179,873	199,970
Total assets	759,708	795,146
U.S.
Segment Reporting Information [Line Items]
Separate account assets	81,217	85,316
Separate account liabilities	81,217	85,316
Total assets	$ 282,741	$ 291,483
Net investment income from equity method investments	23.00%	5.00%	6.00%
Asia
Segment Reporting Information [Line Items]
Separate account assets	$ 10,241	$ 10,825
Separate account liabilities	10,241	10,825
Total assets	$ 169,291	$ 173,884
Net investment income from equity method investments	30.00%	12.00%	9.00%
Latin America
Segment Reporting Information [Line Items]
Separate account assets	$ 37,632	$ 50,073
Separate account liabilities	37,632	50,073
Total assets	$ 59,763	$ 75,047
Net investment income from equity method investments	7.00%	1.00%	2.00%
EMEA
Segment Reporting Information [Line Items]
Separate account assets	$ 3,098	$ 6,083
Separate account liabilities	3,098	6,083
Total assets	27,038	28,372
MetLife Holdings
Segment Reporting Information [Line Items]
Separate account assets	47,685	47,673
Separate account liabilities	47,685	47,673
Total assets	$ 179,551	$ 184,566
Net investment income from equity method investments	26.00%	5.00%	5.00%
Corporate & Other
Segment Reporting Information [Line Items]
Separate account assets	$ 0	$ 0
Separate account liabilities	0	0
Total assets	$ 41,324	$ 41,794

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