Borrowings - Short-Term Debt (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Short-term debt disclosures
Commercial paper	$ 7,871	$ 2,995
Short-term loans	192	161
Long-term debt - current maturities	6,530	7,051
Total	14,594	$ 10,207
Issuance of commercial paper	$ 4,900
Commercial paper
Short-term debt disclosures
Weighted-average interest rates for short-term debt (as a percent)	2.50%	2.50%
Short-term loans
Short-term debt disclosures
Weighted-average interest rates for short-term debt (as a percent)	5.00%	4.30%

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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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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Amount of borrowings from a bank classified as other, maturing within one year or operating cycle, if longer.

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

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