Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Federal
Current	$ 368	$ 312	$ 588	$ 546
Deferred	(31)	17	85	36
Federal income tax	337	329	673	582
State
Current	110	62	140	154
Deferred	2	50	14	67
State income tax	112	112	154	221
Applicable income taxes	$ 449	$ 441	$ 827	$ 803

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

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