Income Taxes - Narrative (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure
U.S. federal statutory income tax rate		35.00%	35.00%	35.00%
Valuation allowance, deferred tax assets		$ 240	$ 205
Cumulative stock ownership change threshold		50.00%
Change in ownership percentage over period		3 years
Foreign income before provision for income taxes		$ 6,150	3,392	$ (8)
Estimated tax liability upon repatriation of earnings from foreign jurisdictions		357	15
Foreign earnings subject to indefinite reinvestment		2,870
Unrecognized tax benefits, interest and penalties accrued		80	36
Unrecognized tax benefits		3,309	$ 3,017	$ 1,682	$ 1,316
Unrecognized tax benefits that would impact effective tax rate		2,580
Internal Revenue Service (IRS)
Income Tax Disclosure
Operating loss carryforwards		$ 3,140
Operating loss carryforwards expiration year		2033
Tax credit carryforward		$ 312
Tax credit carryforward expiration year		2033
State and Local Jurisdiction
Income Tax Disclosure
Operating loss carryforwards		$ 2,770
Operating loss carryforwards expiration year		2032
Tax credit carryforward		$ 1,060
Tax credit carryforward expiration year		2030
Minimum
Income Tax Disclosure
Income tax examination, estimate of possible additional tax liability	$ 3,000
Maximum
Income Tax Disclosure
Income tax examination, estimate of possible additional tax liability	$ 5,000