Property, Equipment and Technology, Net - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Finite-Lived Intangible Assets [Line Items]
Technology, accumulated amortization	$ 1,900	$ 1,700
Depreciation and amortization	613	556	$ 502	[1]
Depreciation and amortization, amortization expense on technology	55	56	50
Property, Equipment and Technology
Finite-Lived Intangible Assets [Line Items]
Depreciation and amortization	558	500	452
Technology and Software
Finite-Lived Intangible Assets [Line Items]
Depreciation and amortization, amortization expense on technology	$ 312	$ 285	$ 259

[1] The Company did not include Visa Europe’s financial results in the Company’s consolidated statements of operations from the acquisition date, June 21, 2016, through June 30, 2016 as the impact was immaterial. The Company’s consolidated statement of operations for the year ended September 30, 2016 includes Visa Europe’s financial results for the three months ended September 30, 2016.