INCOME TAXES - Income Tax Expense (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Current income taxes: Federal taxes	$ 18	$ 17
Current income taxes: State taxes	2	2
Total current income taxes	20	19
Deferred income taxes: Federal taxes	2	2
Total deferred income taxes	2	2
Income taxes	$ 22	$ 21
Statutory tax rate	21.00%	21.00%
Effective tax rate	19.30%	19.70%

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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