ACQUISITIONS, GOODWILL AND OTHER INTANGIBLE ASSETS - ACQUISITIONS (Narrative) (Details) - USD ($) $ in Millions					3 Months Ended	6 Months Ended
	May 23, 2017	Apr. 20, 2017	Aug. 16, 2016	May 10, 2016	Mar. 31, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Business Acquisition [Line Items]
Payment for acquisition						$ 2,643	$ 206
Goodwill						$ 72,335		$ 70,438
LM Wind Power
Business Acquisition [Line Items]
Payment for acquisition		$ 1,700
Goodwill		1,200
Amortizable intangible assets		$ 200
ServiceMax
Business Acquisition [Line Items]
Payment for acquisition					$ 866
Goodwill					670
Amortizable intangible assets					$ 280
Additional ownership interest acquired (as a percent)					96.00%
Cash acquired					$ 91
Equity interest prior to acquisition (as a percent)					4.00%
Doosan
Business Acquisition [Line Items]
Payment for acquisition			$ 220	$ 250
Goodwill	$ 170
Amortizable intangible assets	$ 35
Additional ownership interest acquired (as a percent)	15.00%
Equity interest prior to acquisition (as a percent)			80.00%
Consideration for remaining HRSG business	$ 35
Remaining business subject to local regulatory requirements (as a percent)	5.00%