Intangible Assets and Goodwill - Schedule of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Goodwill [Roll Forward]
Balance as of beginning of period	$ 17,997	$ 17,787
Goodwill from acquisitions	790	0
Foreign currency translation	154	210
Balance as of end of period	$ 18,941	$ 17,997