EMPLOYEE BENEFIT PLANS - AMOUNTS RECOGNIZED IN CONSOLIDATED BALANCE SHEETS (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Liability, Defined Benefit Plan [Abstract]
Accrued benefit liability-long term	$ 503	$ 453
Qualified Defined Benefit [Member]
Liability, Defined Benefit Plan [Abstract]
Accrued benefit liability-long term	392	335
Plan assets-long term (within Other noncurrent assets)	(25)	(31)
Total liability recognized	367	304
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Prior service credit	(8)	(9)
Net loss	607	597
Amount recognized in AOCL (pretax)	$ 599	$ 588

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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- Definition

Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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- Definition

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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