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

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

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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, 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 and lease obligation, including portion classified as current.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt - Debt Instruments (Details)	Sep. 30, 2020 USD ($)	Sep. 30, 2020 GBP (£)	Sep. 30, 2019 USD ($)	Oct. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Debt				$ 400,000,000
Total debt	$ 4,119,520,000		$ 4,172,892,000
Total, net of current portion	3,618,261,000		4,033,880,000
Revolving credit note
Debt Instrument [Line Items]
Maximum borrowing capacity	75,000,000
Debt	0		0
Term loans due in 2020
Debt Instrument [Line Items]
Debt	399,982,000		399,778,000
Overdraft facility due in 2021
Debt Instrument [Line Items]
Maximum borrowing capacity \| £		£ 30,000,000
Debt	0		32,573,000
Receivables securitization facility due 2022
Debt Instrument [Line Items]
Maximum borrowing capacity	1,450,000,000
Debt	350,000,000		350,000,000
Multi-currency revolving credit facility due 2021
Debt Instrument [Line Items]
Maximum borrowing capacity	1,400,000,000
Debt	0		0
$500,000, 3.50% senior notes due 2021
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	3.50%	3.50%
Debt	$ 0		498,908,000
$500,000, 3.40% senior notes due 2024
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	3.40%	3.40%
Debt	$ 498,232,000		497,744,000
$500,000, 3.25% senior notes due 2025
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	3.25%	3.25%
Debt	$ 496,990,000		496,311,000
$750,000, 3.45% senior notes due 2027
Debt Instrument [Line Items]
Principal amount	$ 750,000,000				$ 750,000,000
Interest rate	3.45%	3.45%			3.45%
Debt	$ 743,940,000		743,099,000
$500,000, 2.80% senior notes due 2030
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	2.80%	2.80%
Debt	$ 494,045,000		0
$500,000, 4.25% senior notes due 2045
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	4.25%	4.25%
Debt	$ 494,730,000		494,514,000
$500,000, 4.3% senior notes due 2047
Debt Instrument [Line Items]
Principal amount	$ 500,000,000				$ 500,000,000
Interest rate	4.30%	4.30%			4.30%
Debt	$ 492,755,000		492,488,000
Non-recourse Debt
Debt Instrument [Line Items]
Debt	148,846,000		167,477,000
Less nonrecourse current portion	101,277,000		106,439,000
Corporation Debt
Debt Instrument [Line Items]
Less nonrecourse current portion	$ 399,982,000		$ 32,573,000