Insurance (Guarantees Related to Universal and Variable Life Contracts) (Details) - Universal and Variable Life Contracts - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Secondary Guarantees
Net Amount at Risk by Product and Guarantee [Line Items]
Total account value (1), (3)	$ 13,068	$ 13,678
Net amount at risk (7)	$ 78,887	$ 78,762
Average attained age of policyholders	54 years	55 years
Paid-Up Guarantees
Net Amount at Risk by Product and Guarantee [Line Items]
Total account value (1), (3)	$ 2,658	$ 2,694
Net amount at risk (7)	$ 12,422	$ 12,657
Average attained age of policyholders	66 years	66 years