Intangible assets and goodwill (Details 2 Goodwill) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 02, 2018
Goodwill by reportable segment
Goodwill impairment charge	$ 0	$ 0	$ 0
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	7,414	7,397
Impairments, beginning of year	(1,197)	(1,197)
Goodwill, Acquired	0	127
Other Adjustments	(21)	(110)
Goodwill, end of year	7,393	7,414	7,397
Impairments, end of year	(1,197)	(1,197)	(1,197)
Net goodwill	6,196	6,217	6,200
Construction Industries
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	304	305
Impairments, beginning of year	(22)	(22)
Goodwill, Acquired	0	0
Other Adjustments	2	(1)
Goodwill, end of year	306	304	305
Impairments, end of year	(22)	(22)	(22)
Net goodwill	284	282	283
Resource Industries
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	4,172	4,232
Impairments, beginning of year	(1,175)	(1,175)
Goodwill, Acquired	0	0
Other Adjustments	(16)	(60)
Goodwill, end of year	4,156	4,172	4,232
Impairments, end of year	(1,175)	(1,175)	(1,175)
Net goodwill	2,981	2,997	3,057
Energy & Transportation
Goodwill by reportable segment
Goodwill acquired in business combination				$ 127
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	2,882	2,806
Goodwill, Acquired	0	127
Other Adjustments	(7)	(51)
Goodwill, end of year	2,875	2,882	2,806
All Other
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	56	54
Goodwill, Acquired	0	0
Other Adjustments	0	2
Goodwill, end of year	$ 56	$ 56	$ 54
ECM S.p.A.
Goodwill by reportable segment
Goodwill acquired in business combination				109
Downer Freight Rail
Goodwill by reportable segment
Goodwill acquired in business combination				$ 18

Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

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