INCOME TAXES - Income Tax Expense (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Current income taxes: Federal taxes	$ 19	$ 39	$ 40	$ 46
Current income taxes: State taxes	1	3	3	5
Total current income taxes	20	42	43	51
Deferred income taxes: Federal taxes	4	(26)	3	(24)
Deferred income taxes: State taxes	1	0	1	0
Total deferred income taxes	5	(26)	4	(24)
Income taxes	$ 25	$ 16	$ 47	$ 27
Statutory tax rate	21.00%	21.00%	21.00%	21.00%
Effective tax rate	19.70%	16.00%	19.30%	17.00%

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

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