Borrowings (Annual Maturities on Long-term Debt Outstanding) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
2020	$ 700
2021	1,200
2022	256
2023	800
2024	500
Thereafter	5,125
Total maturities	8,581
Unamortized discount, net	(14)	$ (14)
Debt issuance costs	(45)	(37)
Total long-term debt	$ 8,522	$ 7,430

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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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Amount of long-term debt and lease obligation, classified as noncurrent.

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