Retirement Plans - Schedule of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Retirement Benefits [Abstract]
Service cost	$ 1	$ 2	$ 5	$ 6
Interest cost	2	3	8	7
Expected return on plan assets	(3)	(6)	(11)	(14)
Net actuarial and settlement/curtailment (gain) loss	(3)	(1)	(3)	(1)
Net periodic benefit cost	$ (3)	$ (2)	$ (1)	$ (2)