Debt and Other Obligations - Additional Information (Detail) - USD ($)	1 Months Ended			12 Months Ended
	Sep. 30, 2016	Nov. 30, 2013	Jul. 31, 2012	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Debt Instrument [Line Items]
Long-term debt				$ 908,000,000
Unsecured medium term notes outstanding issued	$ 53,000,000			$ 53,000,000	$ 53,000,000
Maturity of the total outstanding medium term notes, years				4 years
Weighted average interest of medium term notes				7.65%
Capital lease obligations	13,000,000			$ 13,000,000	13,000,000
Repayments of long-term capital lease obligations				$ 20,000,000
Repayment period of capital lease obligation, years				16 years
Payment towards imputed interest				$ 7,000,000
Original cost of capital lease assets	18,000,000			20,000,000	18,000,000
Accumulated depreciation of assets under capital leases	10,000,000			12,000,000	10,000,000
Unsecured short term notes payable to bank	$ 7,000,000			$ 7,000,000	$ 7,000,000
Debt instrument maturity date				1 year
Weighted-average interest rate	9.50%			8.10%	9.50%
Revolving credit facility, committed amount				$ 1,000,000,000
Commercial paper notes outstanding	$ 7,000,000			7,000,000	$ 7,000,000
NHUMO [Member]
Debt Instrument [Line Items]
Preferred stock issued on acquisition		$ 25,000,000
Dividend percentage of preferred stock		6.00%
Dividend payment					1,500,000	$ 1,500,000	$ 1,500,000
Dividends payable, accrued				1,500,000
NHUMO [Member] | Carrying Value [Member]
Debt Instrument [Line Items]
Preferred stock redemption amount		$ 25,000,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper notes outstanding	0			0	0
Chinese Renminbi Debt Due Fiscal 2018 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 4,000,000			$ 5,000,000	$ 4,000,000
Debt instrument due, year				2018	2018
Debt instrument, interest rate	4.75%			4.75%	4.75%
2.55% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2018	2018
Debt maturity date				Jan. 15, 2018
Debt instrument, interest rate	2.55%			2.55%	2.55%
Registered notes issued			$ 250,000,000
Issuance of notes, discount recorded			$ 1,000,000
Proceeds from issuance of debt notes				$ 248,000,000
2.55% Notes Due 2018 [Member] | Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2018
Debt instrument, interest rate			2.55%
3.7% Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2022	2022
Debt maturity date				Jul. 15, 2022
Debt instrument, interest rate	3.70%			3.70%	3.70%
Registered notes issued			$ 350,000,000
Issuance of notes, discount recorded			$ 1,000,000
Proceeds from issuance of debt notes				$ 347,000,000
3.7% Notes Due 2022 [Member] | Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2022
Debt instrument, interest rate			3.70%
3.4% Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2026	2026
Debt maturity date				Sep. 15, 2026
Debt instrument, interest rate	3.40%			3.40%	3.40%
Registered notes issued	$ 250,000,000
Issuance of notes, discount recorded	$ 1,000,000				$ 1,000,000
Proceeds from issuance of debt notes				$ 248,000,000
3.4% Notes Due 2026 [Member] | Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2026
Debt instrument, interest rate	3.40%				3.40%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Amount available under credit facility				$ 1,000,000,000
Credit agreement maturity date				Oct. 23, 2022
Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Debt instrument due, year				2018
Standby letters of credit, outstanding amount				$ 12,000,000