COMMITMENTS, GUARANTEES, PRODUCT WARRANTIES AND OTHER LOSS CONTINGENCIES - Guarantees (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Guarantor Obligations [Line Items]
Liability for indemnification agreements	$ 18,980	$ 20,837
Credit support
Guarantor Obligations [Line Items]
Commitments	1,504
Liability	46
Indemnification agreements
Guarantor Obligations [Line Items]
Commitments	1,607
Liability	6
Liability for indemnification agreements	136
Required funding under residual value guarantees	200
Indemnification agreements - discontinued operations
Guarantor Obligations [Line Items]
Commitments	1,211
Liability	212
Decrease in maximum potential claim	679
Decrease in related liability	$ 55