REVENUES - Equipment and Services Revenues (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Industrial Segment
Disaggregation of Revenue [Line Items]
Total Revenues	$ 25,517	$ 26,067
Industrial Segment | Equipment Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	11,583	12,103
Industrial Segment | Services Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	13,934	13,964
Power
Disaggregation of Revenue [Line Items]
Total Revenues	5,659	7,222
Power | Equipment Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	2,424	3,524
Power | Services Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	3,235	3,698
Renewable Energy
Disaggregation of Revenue [Line Items]
Total Revenues	1,604	1,646
Renewable Energy | Equipment Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	1,123	1,204
Renewable Energy | Services Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	481	442
Aviation
Disaggregation of Revenue [Line Items]
Total Revenues	7,954	7,112
Aviation | Equipment Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	3,113	2,539
Aviation | Services Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	4,841	4,573
Oil & Gas
Disaggregation of Revenue [Line Items]
Total Revenues	5,616	5,385
Oil & Gas | Equipment Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	2,269	2,229
Oil & Gas | Services Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	3,347	3,156
Healthcare
Disaggregation of Revenue [Line Items]
Total Revenues	4,683	4,702
Healthcare | Equipment Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	2,653	2,607
Healthcare | Services Revenues
Disaggregation of Revenue [Line Items]
Total Revenues	$ 2,029	$ 2,095