Equity and Noncontrolling Interests - Schedule of Changes in Redeemable Noncontrolling Interest (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance		$ 318		$ 318
Dividends	$ (14)		$ (2)	(18)	$ (6)
Ending balance	327			327
Restatement Adjustment
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net income		5
Redeemable Noncontrolling Interest
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	57	57	45	57	45
Net income	7		9	20	16
Dividends	0		0	(21)	(18)
Foreign currency translation adjustments	(6)		1	2	12
Ending balance	$ 58	$ 57	$ 55	$ 58	$ 55