Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Current:
Federal	$ 0	$ (9)	$ (28)	$ (15)
State	(1)	0	0	0
Total	(1)	(9)	(28)	(15)
Deferred:
Federal	93	91	(41)	152
State	25	16	(18)	30
Total	118	107	(59)	182
Provision (benefit) for income taxes	$ 117	$ 98	$ (87)	$ 167

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

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