Investments (Leased Real Estate Investments - Operating Leases) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 4,523	$ 5,146
Office
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 2,206	$ 2,322
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Retail
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 804	$ 938
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Apartment
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 625	$ 828
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Land
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 562	$ 635
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Industrial
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 254	$ 339
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Hotel
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 72	$ 84
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Other
Schedule of Operating Leases by Property Type [Line Items]
Leased real estate investments, Carrying Value	$ 0	$ 0
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues
Leased real estate
Schedule of Operating Leases by Property Type [Line Items]
Operating Lease, Lease Income	Total revenues	Total revenues	Total revenues