Reconciliation of Income Tax Expense Computed Using U.S. Statutory Federal Tax Rate to Actual Income Tax Expense (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation Of Income Taxes [Line Items]
Income tax expense at the U.S. federal statutory tax rate	$ 1,758	$ 1,840	$ 1,454
U.S. manufacturing deduction benefit	(126)	(127)	(100)
Tax deductible dividends	(87)	(82)	(77)
Research and development tax credit	(71)	(66)	(96)
Goodwill impairment - non-deductible portion		30	50
Other, net	(56)	49	(26)
Total income tax expense	$ 1,418	$ 1,644	$ 1,205