Long-Term Debt and Short-Term Borrowings - Future Maturities of Long-term Debt (Details) $ in Millions	Mar. 31, 2021 USD ($)
Maturities of long-term debt
Remainder of 2021	$ 763
2022	1,256
2023	1,945
2024	1,100
2025	1,791
2026	1,516
After 2026	9,798
Total long-term debt	$ 18,169

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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