Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Federal
Current	$ 315	$ 220
Deferred	(106)	116
Federal income tax	209	336
State
Current	70	30
Deferred	(19)	12
State income tax	51	42
Applicable income taxes	$ 260	$ 378

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

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