Short-term borrowings (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Short-term borrowings:
Short-term borrowings	$ 7,303	$ 6,967
Notes payable to banks
Short-term borrowings:
Weighted-average interest rates on short-term borrowings (as a percent)	7.00%	9.20%
Commercial paper
Short-term borrowings:
Weighted-average interest rates on short-term borrowings (as a percent)	0.90%	0.50%
Demand notes
Short-term borrowings:
Weighted-average interest rates on short-term borrowings (as a percent)	0.90%	0.80%
Machinery, Energy & Transportation
Short-term borrowings:
Short-term borrowings	$ 209	$ 9
Machinery, Energy & Transportation | Notes payable to banks
Short-term borrowings:
Short-term borrowings	59	9
Machinery, Energy & Transportation | Commercial paper
Short-term borrowings:
Short-term borrowings	150	0
Financial Products
Short-term borrowings:
Short-term borrowings	7,094	6,958
Financial Products | Notes payable to banks
Short-term borrowings:
Short-term borrowings	553	440
Financial Products | Commercial paper
Short-term borrowings:
Short-term borrowings	5,985	5,811
Financial Products | Demand notes
Short-term borrowings:
Short-term borrowings	$ 556	$ 707