EMPLOYEE BENEFITS - Changes in the Fair Value of Pension Plan Assets, Projected Benefit Obligation, Funded Status, and Accumulated Benefit Obligation (Details) - USD ($) $ in Millions		12 Months Ended
	Sep. 07, 2016	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets as of January 1		$ 104
Fair value of plan assets as of December 31		114	$ 104
Qualified Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets as of January 1		1,015	917
Actual return on plan assets		185	82
Employer contributions	$ 75	0	75
Benefits and administrative expenses paid		(61)	(59)
Fair value of plan assets as of December 31		1,139	1,015
Projected benefit obligation		1,089	1,024
Pension asset (obligation)		50	(9)
Accumulated benefit obligation		1,089	1,024
Non-Qualified Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets as of January 1		0	0
Actual return on plan assets		0	0
Employer contributions		8	8
Benefits and administrative expenses paid		(8)	(8)
Fair value of plan assets as of December 31		0	0
Projected benefit obligation		106	105
Pension asset (obligation)		(106)	(105)
Accumulated benefit obligation		$ 106	$ 105