EXIT COSTS AND RESTRUCTURING RESERVES - Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1us-gaap_RestructuringCosts	$ 101us-gaap_RestructuringCosts
Restructuring Reserve, Accrual Adjustment	2	10
Expected restructuring cost	18
Restructuring charges incurred	3us-gaap_RestructuringCharges	124us-gaap_RestructuringCharges
Outside Services
Restructuring Cost and Reserve [Line Items]
Restructuring costs	1	24
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring costs		12
Restructuring charges incurred		7
Employee Severance
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost	13
Employee Severance \| Salaries & Employee Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring costs		41
Restructuring Reserve, Accrual Adjustment	2	1
Restructuring charges incurred	0	43
Facility Closing
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost	3
Facility Closing \| Occupancy & Equipment
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2	18
Restructuring Reserve, Accrual Adjustment	0	5
Restructuring charges incurred	2	24
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost	2
Building Impairment \| Occupancy & Equipment
Restructuring Cost and Reserve [Line Items]
Impairment charges		6
Spinoff
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred		17
Employee Severance \| Salaries & Employee Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred		3
Facility Closing \| Occupancy & Equipment
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred		3
Facility Closing \| Outside Services
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred		4
Software expense \| Amortization of software
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 6

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for a specified type of restructuring cost, excluding adjustments for costs incurred during the period, costs settled during the period, and foreign currency translation adjustments.

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