INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax expense	$ 124	$ 144	$ 237	$ 258
Effective income tax rate	22.60%	31.10%	22.60%	28.80%
U.S. Federal income tax expense and tax rate			21.00%	35.00%
Deferred taxes, net	$ 456		$ 456		$ 571