Investments (Leased Real Estate Investments - Operating Leases) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 5,146	$ 5,450
Office
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	2,322	2,351
Operating Lease, Lease Income	196	188	$ 175
Retail
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	938	1,147
Operating Lease, Lease Income	75	93	102
Apartment
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	828	810
Operating Lease, Lease Income	66	62	24
Land
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	635	621
Operating Lease, Lease Income	28	25	21
Industrial
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	339	332
Operating Lease, Lease Income	58	56	46
Hotel
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	84	96
Operating Lease, Lease Income	6	5	7
Other
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	0	93
Operating Lease, Lease Income	0	6	5
Leased real estate investments
Schedule of Operating Leases by Property Type [Line Items]
Operating Lease, Lease Income	$ 429	$ 435	$ 380