Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Federal
Current	$ 350	$ 704	$ 703	$ 1,019
Deferred	76	(659)	206	(765)
Federal income tax	426	45	909	254
State
Current	109	136	203	206
Deferred	16	(117)	46	(136)
State income tax	125	19	249	70
Applicable income taxes	$ 551	$ 64	$ 1,158	$ 324

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

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