Business Transformation Initiatives (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Costs principally comprising consulting, advisory and employee-related costs		$ 87	$ 62
Restructuring, Incurred Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, General and Administrative Expense	Selling, General and Administrative Expense
Corporate Services Member
Restructuring Cost and Reserve [Line Items]
Costs principally comprising consulting, advisory and employee-related costs	$ 9	$ 14
Restructuring, Incurred Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, General and Administrative Expense	Selling, General and Administrative Expense