Provision for Federal & Foreign Income Tax Expense (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Federal income tax expense (benefit):
Current	$ 1,327	$ 1,573	$ 1,770
Deferred	(231)	(473)	(351)
Total federal income tax expense	1,096	1,100	1,419
Foreign income tax expense (benefit):
Current	56	39	13
Deferred	(19)	34	(8)
Total foreign income tax expense	37	73	5
Total income tax expense	$ 1,133	$ 1,173	$ 1,424

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

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