CONTRACT BALANCES - Conifer Segment (Details) - Conifer - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Receivables
Beginning balance	$ 26	$ 42
Ending balance	23	90
Increase/(decrease)	(3)	48
Contract Asset-Unbilled Revenue
Beginning balance	11	11
Ending balance	7	11
Increase/(decrease)	(4)	0
Contract Liability-Current Deferred Revenue
Balance at beginning of period	61	61
Balance at end of period	61	64
Contract Liability-Long-term Deferred Revenue
Balance at beginning of period	18	20
Balance at end of period	17	20
Amount of revenue recognized included in current deferred revenue liability	54	49
Short-term Contract with Customer
Contract Liability-Current Deferred Revenue
Increase/(decrease)	0	3
Contract Liability-Long-term Deferred Revenue
Increase/(decrease)	0	3
Long-term Contract with Customer
Contract Liability-Current Deferred Revenue
Increase/(decrease)	(1)	0
Contract Liability-Long-term Deferred Revenue
Increase/(decrease)	$ (1)	$ 0

Change In Contract With Customer, Asset, Net, Current [Roll Forward]

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Change In Contract With Customer, Asset, Net, Noncurrent [Roll Forward]

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Change In Contract With Customer, Liability, Net, Current [Roll Forward]

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Change In Contract With Customer, Liability, Net, Noncurrent [Roll Forward]

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Contract With Customer, Asset, Net, Current, Period Increase (Decrease)

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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