Ability to Increase Debt Commitment Under Accordion Feature in December and March Quarters

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Debt Instrument, Face Amount Percentage

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Percentage of principal amount of debt redeemed.

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No definition available.

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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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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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- Definition

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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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Debt - Additional Information (Details)		1 Months Ended		12 Months Ended
Debt - Additional Information (Details)	Sep. 30, 2020 USD ($)	May 31, 2020 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2020 GBP (£)	Oct. 31, 2018 USD ($)
Debt Instrument [Line Items]
Long-term debt								$ 400,000,000
Payment of premium on early retirement of debt			$ 22,300,000	$ 21,448,000	$ 0	$ 22,348,000
Scheduled future principal payments, in fiscal 2021	$ 493,100,000			493,100,000
Scheduled future principal payments, in fiscal 2022	383,900,000			383,900,000
Scheduled future principal payments, in fiscal 2023	8,000,000.0			8,000,000.0
Scheduled future principal payments, in fiscal 2024	503,700,000			503,700,000
Scheduled future principal payments, in fiscal 2025	500,000,000.0			500,000,000.0
Scheduled future principal payments, thereafter	2,300,000,000			2,300,000,000
Interest paid				150,700,000	167,400,000	162,100,000
Amortization of financing fees and accretion of original issue discounts				6,400,000	7,100,000	$ 7,700,000
Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,400,000,000			1,400,000,000
Facility fee, period end	0.09%
Long-term debt	$ 0			0	0
Commercial paper
Debt Instrument [Line Items]
Maximum borrowing capacity	1,400,000,000			1,400,000,000
Short-term debt	0			0	0
Receivables securitization facility due 2022
Debt Instrument [Line Items]
Maximum borrowing capacity	1,450,000,000			1,450,000,000
Accordion feature, potential increase in commitment	250,000,000			250,000,000
Long-term debt	350,000,000			350,000,000	350,000,000
Revolving credit note
Debt Instrument [Line Items]
Maximum borrowing capacity	75,000,000			75,000,000
Long-term debt	0			0	0
Overdraft facility due in 2021
Debt Instrument [Line Items]
Maximum borrowing capacity \| £							£ 30,000,000
Long-term debt	0			0	32,573,000
Term Loan Agreement October 2018
Debt Instrument [Line Items]
Principal amount								$ 400,000,000
$500,000, 2.80% senior notes due 2030
Debt Instrument [Line Items]
Long-term debt	494,045,000			494,045,000	0
Principal amount	$ 500,000,000			$ 500,000,000
Interest rate	2.80%			2.80%			2.80%
$500,000, 2.80% senior notes due 2030 \| Notes Payable to Banks
Debt Instrument [Line Items]
Principal amount		$ 500,000,000
Interest rate		2.80%
Debt instrument, redemption price, percentage of principal amount redeemed		99.71%
Effective yield percentage		2.81%
$500,000, 3.50% senior notes due 2021
Debt Instrument [Line Items]
Long-term debt	$ 0			$ 0	498,908,000
Principal amount	$ 500,000,000			$ 500,000,000
Interest rate	3.50%			3.50%			3.50%
$500,000, 3.50% senior notes due 2021 \| Notes Payable to Banks
Debt Instrument [Line Items]
Principal amount		$ 500,000,000
Interest rate		3.50%
Payment of premium on early retirement of debt		$ 21,400,000
$750,000, 3.45% senior notes due 2027
Debt Instrument [Line Items]
Long-term debt	$ 743,940,000			$ 743,940,000	743,099,000
Principal amount	$ 750,000,000		$ 750,000,000	$ 750,000,000
Interest rate	3.45%		3.45%	3.45%			3.45%
Effective yield percentage			3.48%
Percentage of principal amount			99.76%
$500,000, 4.3% senior notes due 2047
Debt Instrument [Line Items]
Long-term debt	$ 492,755,000			$ 492,755,000	$ 492,488,000
Principal amount	$ 500,000,000		$ 500,000,000	$ 500,000,000
Interest rate	4.30%		4.30%	4.30%			4.30%
Effective yield percentage			4.33%
Percentage of principal amount			99.51%
$400,000, 4.875% senior notes due 2019
Debt Instrument [Line Items]
Principal amount			$ 400,000,000
Interest rate			4.875%
Minimum \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Facility fee, period end				0.05%
Maximum \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Facility fee, period end				0.125%
CDOR / LIBOR / EURIBOR / Bankers Acceptance Stamping Fee \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Variable rate spread	0.91%
CDOR / LIBOR / EURIBOR / Bankers Acceptance Stamping Fee \| Minimum \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Variable rate spread				0.70%
CDOR / LIBOR / EURIBOR / Bankers Acceptance Stamping Fee \| Maximum \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Variable rate spread				1.125%
Alternate base rate and Canadian prime rate \| Minimum \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Variable rate spread				0.00%
Alternate base rate and Canadian prime rate \| Maximum \| Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Variable rate spread				0.125%