Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Income Tax Contingency [Line Items]
Effective tax rate	16.20%	21.20%
Provision for tax benefits related to settlement of employee awards	$ 53	$ 49
Provision for income taxes	112	$ 279
Liability for unrecognized tax benefits	525		$ 550
Unrecognized tax benefits, accrued interest	65		62
Unrecognized tax benefits that would impact effective tax rate	$ 158		$ 160