Borrowings - Contractual Maturities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Contractual maturities of long-term debt
2020 (Q2-Q4)	$ 5,049
2021	5,748
2022	2,365
2023	1,461
2024	205
2025 and beyond	56
Total	14,884
Debt
Contractual maturities of long-term debt
2020 (Q2-Q4)	1,839
2021	3,133
2022	603
2023	786
2024	5
2025 and beyond	0
Total	6,367	$ 6,495
Debt payable to IBM
Contractual maturities of long-term debt
2020 (Q2-Q4)	3,210
2021	2,615
2022	1,761
2023	675
2024	201
2025 and beyond	56
Total	$ 8,517

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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