Debt (Maturities) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Scheduled maturities of debt
Total installments of debt	$ 8,011	$ 9,361
Total Installments
Scheduled maturities of debt
2021	652
2022	637
2023	1,325
2024	685
2025	670
Thereafter	4,532
Total installments of debt	8,501
Total debt-related balances, net	(67)
Total carrying amount of debt	8,434
Principal installments
Scheduled maturities of debt
2021	585
2022	561
2023	1,249
2024	608
2025	593
Thereafter	4,415
Total installments of debt	8,011
Other installments
Scheduled maturities of debt
2021	67
2022	76
2023	76
2024	77
2025	77
Thereafter	117
Total installments of debt	$ 490

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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