Property, Equipment and Technology, Net - Summary of Property, Equipment and Technology, Net (Detail) - USD ($) $ in Millions |
Sep. 30, 2019 |
Sep. 30, 2018 |
|---|---|---|
| Property, Plant and Equipment [Line Items] | ||
| Total property, equipment and technology | $ 6,570 | $ 5,697 |
| Accumulated depreciation and amortization | (3,875) | (3,225) |
| Property, equipment and technology, net | 2,695 | 2,472 |
| Land | ||
| Property, Plant and Equipment [Line Items] | ||
| Total property, equipment and technology | 71 | 69 |
| Buildings and building improvements | ||
| Property, Plant and Equipment [Line Items] | ||
| Total property, equipment and technology | 965 | 898 |
| Furniture, equipment and leasehold improvements | ||
| Property, Plant and Equipment [Line Items] | ||
| Total property, equipment and technology | 1,913 | 1,661 |
| Construction-in-progress | ||
| Property, Plant and Equipment [Line Items] | ||
| Total property, equipment and technology | 180 | 153 |
| Technology | ||
| Property, Plant and Equipment [Line Items] | ||
| Total property, equipment and technology | $ 3,441 | $ 2,916 |