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Intangible Assets and Goodwill (Details 2) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jan. 02, 2018
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of period	$ 7,397
Impairments, beginning of period	(1,197)
Net goodwill, beginning of period	6,200
Goodwill Acquired	121
Goodwill impairment charge	0	$ 0
Other adjustments	(88)
Goodwill, end of period	7,430
Impairments, end of period	(1,197)
Net goodwill, end of period	6,233
Goodwill	6,200
Construction Industries
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of period	305
Impairments, beginning of period	(22)
Net goodwill, beginning of period	283
Goodwill Acquired	0
Other adjustments	0
Goodwill, end of period	305
Impairments, end of period	(22)
Net goodwill, end of period	283
Goodwill	283
Resource Industries
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of period	4,232
Impairments, beginning of period	(1,175)
Net goodwill, beginning of period	3,057
Goodwill Acquired	0
Other adjustments	(46)
Goodwill, end of period	4,186
Impairments, end of period	(1,175)
Net goodwill, end of period	3,011
Goodwill	3,057
Energy & Transportation
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of period	2,806
Goodwill Acquired	121
Other adjustments	(44)
Goodwill, end of period	2,883
All Other
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of period	54
Goodwill Acquired	0
Other adjustments	2
Goodwill, end of period	$ 56
ECM S.p.A.
Changes in carrying amount of goodwill by reportable segment:
Goodwill			$ 109
Downer Freight Rail
Changes in carrying amount of goodwill by reportable segment:
Goodwill			$ 12