Debt instrument due year.

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- Definition

Payment towards imputed interest.

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Repayment period of capital lease obligation.

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Weighted average interest rate of medium term notes.

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Weighted average maturity of outstanding medium term notes.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt discount.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, carrying value at the balance sheet date of a financial instrument used to receive debt funding on a regular basis with original maturities ranging from 5-10 years.

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The fair value of notes issued in noncash investing and financing activities.

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The cash outflow for reacquisition of callable preferred stock.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The percentage rate used to calculate dividend payments on preferred stock.

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The redemption (or callable) amount of currently redeemable preferred stock. Includes amounts representing dividends not currently declared or paid but which will be payable under the redemption features or for which ultimate payment is solely within the control of the issuer.

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The cash inflow from borrowings supported by a written promise to pay an obligation that is uncollateralized (where debt is not backed by the pledge of collateral).

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The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer).

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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Debt and Other Obligations - Additional Information (Detail) - USD ($)	1 Months Ended				12 Months Ended
	Nov. 30, 2018	Sep. 30, 2016	Nov. 30, 2013	Jul. 31, 2012	Sep. 30, 2018	Sep. 30, 2017
Debt Instrument [Line Items]
Revolving credit facility, committed amount					$ 1,000,000,000
Long-term debt					747,000,000
Unsecured medium term notes outstanding issued					$ 53,000,000	$ 53,000,000
Maturity of the total outstanding medium term notes, years					3 years
Weighted average interest of medium term notes					7.65%
Capital lease obligations					$ 11,000,000	13,000,000
Repayments of long-term capital lease obligations					$ 17,000,000
Repayment period of capital lease obligation, years					15 years
Payment towards imputed interest					$ 6,000,000
Original cost of capital lease assets					20,000,000	20,000,000
Accumulated depreciation of assets under capital leases					13,000,000	12,000,000
Short-term borrowings					249,000,000	7,000,000
NHUMO [Member]
Debt Instrument [Line Items]
Dividend percentage of preferred stock			6.00%
NHUMO [Member] \| Carrying Value [Member]
Debt Instrument [Line Items]
Preferred stock redemption amount			$ 25,000,000
Subsequent Event [Member] \| NHUMO [Member]
Debt Instrument [Line Items]
Preferred stock redemption option exercised	$ 25,000,000
Payments of dividends	$ 1,400,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Short-term borrowings					$ 249,000,000	0
Weighted-average interest rate					2.36%
Short-term Notes Payable [Member]
Debt Instrument [Line Items]
Short-term borrowings					$ 0	$ 7,000,000
Weighted-average interest rate						8.10%
Debt instrument maturity date						1 year
Chinese Renminbi Debt [Member]
Debt Instrument [Line Items]
Long-term debt					$ 4,000,000	$ 5,000,000
2.55% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt maturity date					Jan. 15, 2018
Debt instrument, interest rate					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
Debt instrument due, year					2018	2018
2.55% Notes Due 2018 [Member] \| Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				2.55%
Debt instrument due, year					2018
3.7% Notes due fiscal 2022 [Member]
Debt Instrument [Line Items]
Debt maturity date					Jul. 15, 2022
Debt instrument, interest rate					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
Debt instrument due, year					2022	2022
3.7% Notes due fiscal 2022 [Member] \| Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				3.70%
Debt instrument due, year					2022
3.4% Notes due fiscal 2026 [Member]
Debt Instrument [Line Items]
Debt maturity date					Sep. 15, 2026
Debt instrument, interest rate					3.40%	3.40%
Registered notes issued		$ 250,000,000
Issuance of notes, discount recorded		$ 1,000,000
Proceeds from issuance of debt notes					$ 248,000,000
Debt instrument due, year					2026	2026
3.4% Notes due fiscal 2026 [Member] \| Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		3.40%
Debt instrument due, year					2026
Revolving Credit Facility, expires fiscal 2023 [Member]
Debt Instrument [Line Items]
Amount available under credit facility					$ 751,000,000
Credit agreement maturity date					Oct. 23, 2022
Debt instrument due, year					2023	2023
Revolving Credit Facility - Canada, expires fiscal 2021 [Member]
Debt Instrument [Line Items]
Credit agreement maturity date					Sep. 24, 2021
Revolving credit facility, committed amount					$ 100,000,000
Credit agreement, available borrowing					$ 10,000,000
Debt instrument due, year					2021	2021
Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Debt instrument due, year					2019
Standby letters of credit, outstanding amount					$ 7,000,000