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Investments (Real Estate and Real Estate Joint Ventures) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Real Estate [Line Items]
Leased real estate investments, Carrying Value	$ 4,416		$ 4,416		$ 5,146
Other real estate investments, Carrying Value	479		479		474
Real estate joint ventures, Carrying Value	7,637		7,637		6,596
Real Estate Investments, Net	12,532		12,532		$ 12,216
Income (Loss) from Equity Method Investments	(135)	$ 1,700	1,300	$ 4,000
Real Estate and Real Estate Joint Ventures
Real Estate [Line Items]
Gross Investment Income, Operating	284	279	991	660
Leased real estate
Real Estate [Line Items]
Operating Lease, Lease Income	95	108	299	327
Other real estate
Real Estate [Line Items]
Operating Lease, Lease Income	89	58	189	144
Real estate joint ventures
Real Estate [Line Items]
Income (Loss) from Equity Method Investments	$ 100	$ 113	$ 503	$ 189