GOODWILL AND OTHER INTANGIBLES - Identifiable Intangible Assets (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 64	$ 67
Accumulated Amortization	(55)	(55)
Net Intangible Assets	9	12
Customer relationships and lists
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	57	60
Accumulated Amortization	(49)	(49)
Net Intangible Assets	8	11
Software
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3	3
Accumulated Amortization	(2)	(2)
Net Intangible Assets	1	1
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4	4
Accumulated Amortization	(4)	(4)
Net Intangible Assets	$ 0	$ 0