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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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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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Debt - Outstanding Amount of Credit Facilities (Details)	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 AUD ($)	Dec. 31, 2021 EUR (€)
Line of Credit Facility [Line Items]
Total unsecured debt	$ 2,690,863,000	$ 2,421,560,000
Unamortized debt issuance costs	(9,136,000)	(8,041,000)
Unamortized discounts	(4,582,000)	(4,156,000)
Total debt	2,677,145,000	2,409,363,000
Less debt due within one year	160,531,000	0
Long-term debt, excluding current portion	2,516,614,000	2,409,363,000
Senior Unsecured Notes, Due November 1, 2030
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 500,000,000
Debt instrument, stated percentage		1.875%	1.875%	1.875%
Long-term debt	500,000,000	$ 500,000,000
Series G Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 50,000,000
Debt instrument, stated percentage		2.64%	2.64%	2.64%
Long-term debt	50,000,000	$ 0
Series F Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 250,000,000
Debt instrument, stated percentage		3.24%	3.24%	3.24%
Long-term debt	250,000,000	$ 250,000,000
Series A Senior Unsecured Notes, Due 2024
Line of Credit Facility [Line Items]
Debt instrument, face amount			$ 155,000,000
Debt instrument, stated percentage		3.10%	3.10%	3.10%
Long-term debt	119,133,000	$ 112,375,000
Series J Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 225,000,000
Debt instrument, stated percentage		1.40%	1.40%	1.40%
Long-term debt	276,773,000	$ 254,835,000
Series B Senior Unsecured Notes, Due 2026
Line of Credit Facility [Line Items]
Debt instrument, face amount			$ 155,000,000
Debt instrument, stated percentage		3.43%	3.43%	3.43%
Long-term debt	119,133,000	$ 112,375,000
Series H Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 250,000,000
Debt instrument, stated percentage		3.24%	3.24%	3.24%
Long-term debt	250,000,000	$ 250,000,000
Series K Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 250,000,000
Debt instrument, stated percentage		1.81%	1.81%	1.81%
Long-term debt	307,525,000	$ 283,150,000
Series I Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 120,000,000
Debt instrument, stated percentage		3.70%	3.70%	3.70%
Long-term debt	120,000,000	$ 120,000,000
Series A Senior Unsecured Notes, Due 2029
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 50,000,000
Debt instrument, stated percentage		1.55%	1.55%	1.55%
Long-term debt	61,505,000	$ 56,630,000
Series L Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 125,000,000
Debt instrument, stated percentage		2.02%	2.02%	2.02%
Long-term debt	153,762,000	$ 141,575,000
Series B Senior Unsecured Notes, Due 2031
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 100,000,000
Debt instrument, stated percentage		1.74%	1.74%	1.74%
Long-term debt	123,010,000	$ 113,260,000
Series M Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 100,000,000
Debt instrument, stated percentage		2.32%	2.32%	2.32%
Long-term debt	123,010,000	$ 113,260,000
Series C Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount \| €				€ 100,000,000
Debt instrument, stated percentage		1.95%	1.95%	1.95%
Long-term debt	123,010,000	$ 113,260,000
Other Unsecured Debt
Line of Credit Facility [Line Items]
Unsecured debt	114,002,000	840,000
Syndicated Facility, Due September 30, 2026 \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	1,500,000,000
Line of credit, current	$ 0	$ 0
London Interbank Offered Rate (LIBOR) \| Syndicated Facility, Due September 30, 2026 \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	1.13%