Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Federal
Current	$ 704	$ 368	$ 1,019	$ 588
Deferred	(659)	(31)	(765)	85
Federal income tax	45	337	254	673
State
Current	136	110	206	140
Deferred	(117)	2	(136)	14
State income tax	19	112	70	154
Applicable income taxes	$ 64	$ 449	$ 324	$ 827

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

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