Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2022	Sep. 30, 2021
Loss Contingencies [Line Items]
Accrued Environmental Loss Contingencies, Current	$ 57	$ 48
Accrued Environmental Loss Contingencies, Noncurrent	15	54
Accrual for Environmental Loss Contingencies, Total	72	102
Conditional asset retirement obligations	25	29
Total asbestos-related assets	318	378
Estimated asbestos related net liability on a discounted basis	125	80
Restricted Cash	35	6
Insurable liabilities, total	332	325
Insurance Settlements Receivable, Current	5	5
Insurance Settlements Receivable, Noncurrent	15	15
Total insurable receivables	20	20
Asbestos Issue [Member]
Loss Contingencies [Line Items]
Other current liabilities	58	58
Other noncurrent liabilities	385	400
Total asbestos-related liabilities	443	458
Restricted Cash	8	6
Restricted Investments	255	314
Total restricted assets	263	320
Insurance recoveries for asbestos-related liabilities	55	58
Other Current Liabilities
Loss Contingencies [Line Items]
Insurable liabilities	91	77
Accrued Compensation and Benefits [Member]
Loss Contingencies [Line Items]
Insurable liabilities	22	22
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Insurable liabilities	219	226
Other Current Assets
Loss Contingencies [Line Items]
Asbestos-related assets, current	39	13
Other Noncurrent Assets
Loss Contingencies [Line Items]
Asbestos-related assets, noncurrent	$ 279	$ 365