Income Tax (Provision for Income Tax from Continuing Operations) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ (35)	$ (178)	$ 368
Foreign	0	0	18
Subtotal	(35)	(178)	386
Deferred:
Federal	(303)	331	(1,124)
Foreign	0	0	0
Subtotal	(303)	331	(1,124)
Current and Deferred
Provision for income tax expense (benefit)	$ (338)	$ 153	$ (738)

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

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