v3.21.1

Debt (Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Scheduled maturities of debt
Total installments of debt	$ 7,249	$ 7,376
Total Installments
Scheduled maturities of debt
2022	537
2023	664
2024	972
2025	593
2026	1,605
Thereafter	3,340
Total installments of debt	7,711
Total debt-related balances, net	(91)
Total carrying amount of debt	7,620
Principal installments
Scheduled maturities of debt
2022	461
2023	588
2024	895
2025	516
2026	1,527
Thereafter	3,262
Total installments of debt	7,249
Other installments
Scheduled maturities of debt
2022	76
2023	76
2024	77
2025	77
2026	78
Thereafter	78
Total installments of debt	$ 462

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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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