ACQUISITIONS, GOODWILL AND OTHER INTANGIBLE ASSETS - Intangible Assets Subject to Amortization (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 30,813	$ 30,618
Accumulated amortization	(13,315)	(12,561)
Net	17,499	18,056
Customer-related
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	10,400	10,614
Accumulated amortization	(3,332)	(3,095)
Net	7,070	7,521
Patents and technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	10,694	10,271
Accumulated amortization	(4,133)	(3,899)
Net	6,561	6,372
Capitalized software
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	8,137	8,064
Accumulated amortization	(5,167)	(4,974)
Net	2,970	3,089
Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,181	1,280
Accumulated amortization	(502)	(421)
Net	679	859
Lease valuations
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	161	170
Accumulated amortization	(85)	(80)
Net	77	89
All other
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	239	218
Accumulated amortization	(96)	(92)
Net	$ 142	$ 125