Derivative financial instruments and risk management (Details 2) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Derivatives Fair Value
Asset Fair Value	$ 95	$ 105
Liability Fair Value	(167)	(56)
Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	23	14
Liability Fair Value	(159)	(46)
Financial Products
Derivatives Fair Value
Asset Fair Value	72	91
Liability Fair Value	(8)	(10)
Designated derivatives
Derivatives Fair Value
Asset (Liability) Fair Value	(87)	35
Undesignated derivatives
Derivatives Fair Value
Asset (Liability) Fair Value	15	14
Foreign exchange contracts | Designated derivatives | Receivables - trade and other | Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	13	12
Foreign exchange contracts | Designated derivatives | Long-term receivables - trade and other | Financial Products
Derivatives Fair Value
Asset Fair Value	29	0
Foreign exchange contracts | Designated derivatives | Accrued expenses | Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	(93)	(25)
Foreign exchange contracts | Designated derivatives | Accrued expenses | Financial Products
Derivatives Fair Value
Liability Fair Value	(3)	0
Foreign exchange contracts | Designated derivatives | Other Liabilities [Member] | Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	(36)	0
Foreign exchange contracts | Undesignated derivatives | Receivables - trade and other | Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	0	2
Foreign exchange contracts | Undesignated derivatives | Receivables - trade and other | Financial Products
Derivatives Fair Value
Asset Fair Value	39	3
Foreign exchange contracts | Undesignated derivatives | Long-term receivables - trade and other | Financial Products
Derivatives Fair Value
Asset Fair Value	0	36
Foreign exchange contracts | Undesignated derivatives | Accrued expenses | Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	(30)	(9)
Foreign exchange contracts | Undesignated derivatives | Accrued expenses | Financial Products
Derivatives Fair Value
Liability Fair Value	(4)	(6)
Interest rate contracts | Designated derivatives | Receivables - trade and other | Financial Products
Derivatives Fair Value
Asset Fair Value	0	1
Interest rate contracts | Designated derivatives | Long-term receivables - trade and other | Financial Products
Derivatives Fair Value
Asset Fair Value	4	51
Interest rate contracts | Designated derivatives | Accrued expenses | Financial Products
Derivatives Fair Value
Liability Fair Value	(1)	(4)
Commodity contracts | Undesignated derivatives | Receivables - trade and other | Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	10	0
Commodity contracts | Undesignated derivatives | Accrued expenses | Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	$ 0	$ (12)