GOODWILL AND INTANGIBLE ASSETS - Other Intangibles (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross	$ 34	$ 2
Accumulated Amortization	3	0
Net	$ 31	2
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Useful life	7 years
Gross	$ 20	0
Accumulated Amortization	1	0
Net	19	0
Acquired relationships
Finite-Lived Intangible Assets [Line Items]
Gross	11	2
Accumulated Amortization	1	0
Net	10	2
Other
Finite-Lived Intangible Assets [Line Items]
Gross	3	0
Accumulated Amortization	1	0
Net	$ 2	$ 0
Minimum | Acquired relationships
Finite-Lived Intangible Assets [Line Items]
Useful life	5 years
Minimum | Other
Finite-Lived Intangible Assets [Line Items]
Useful life	2 years
Maximum | Acquired relationships
Finite-Lived Intangible Assets [Line Items]
Useful life	15 years
Maximum | Other
Finite-Lived Intangible Assets [Line Items]
Useful life	3 years