Investments (Leveraged and Direct Financing Leases - Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Investments, All Other Investments [Abstract]
Loans and Leases Receivable, Other Information	The payment periods for leveraged leases generally range from one to 12 years, but in certain circumstances can be over 12 years, while the payment periods for direct financing leases generally range from one to 17 years.
Leveraged Leases, Net Investment in Leveraged Leases Disclosure, Investment in Leveraged Leases, Net	$ 836	$ 896
Direct Financing Lease, Net Investment in Lease	177	$ 189
Leveraged and Direct Financing Leases, Allowance for credit loss	41
Deferral rental payment for leveraged and direct finance leases	$ 2