BASIS OF PRESENTATION - Other Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Other intangible assets
Gross Carrying Amount	$ 2,766	$ 2,694
Accumulated Amortization	(1,163)	(1,092)
Net Book Value	1,603	1,602
Capitalized software costs
Other intangible assets
Gross Carrying Amount	1,681	1,616
Accumulated Amortization	(977)	(912)
Net Book Value	704	704
Trade names
Other intangible assets
Gross Carrying Amount	102	102
Accumulated Amortization	0	0
Net Book Value	102	102
Contracts
Other intangible assets
Gross Carrying Amount	875	869
Accumulated Amortization	(103)	(94)
Net Book Value	772	775
Other
Other intangible assets
Gross Carrying Amount	108	107
Accumulated Amortization	(83)	(86)
Net Book Value	$ 25	$ 21