Borrowings - Short-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Short-term debt disclosures
Long-term debt - current maturities	$ 6,773	$ 5,214
Total short-term debt	10,932	6,987
Commercial paper
Short-term debt disclosures
Short-term debt	$ 3,986	$ 1,496
Weighted-average interest rates for short-term debt (as a percent)	2.20%	1.50%
Short-term loans
Short-term debt disclosures
Short-term debt	$ 173	$ 276
Weighted-average interest rates for short-term debt (as a percent)	8.30%	8.80%

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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