Debt Debt Table € in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) Rate	Dec. 31, 2020 EUR (€)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Senior Notes	$ 791,102		$ 714,351
Debt issuance costs, net	(2,760)		(2,259)
Other Borrowings	51,970		55,868
Total debt	1,334,491		1,291,218
Less: current portion	(50,317)		(55,868)
Long-term debt	1,284,174		1,235,350
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,100,000
Debt Instrument, Term	10 years
Line of Credit [Member]
Debt Instrument [Line Items]
$1.1 billion Credit Agreement, interest at LIBOR plus 87.5 basis points(1)	$ 491,419		520,999
Debt Instrument, Maturity Date	Jun. 15, 2023
Debt Instrument, Basis Spread on Variable Rate \| Rate	0.875%
Line of Credit Facility, Remaining Borrowing Capacity	$ 602,500
3.67% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 50,000		50,000
Debt Instrument, Interest Rate, Stated Percentage	3.67%	3.67%
Debt Instrument, Maturity Date	Dec. 17, 2022
4.10% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 50,000		50,000
Debt Instrument, Interest Rate, Stated Percentage	4.10%	4.10%
Debt Instrument, Maturity Date	Sep. 19, 2023
Debt Instrument, Term	10 years
3.84% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 125,000		125,000
Debt Instrument, Interest Rate, Stated Percentage	3.84%	3.84%
Debt Instrument, Maturity Date	Sep. 19, 2024
Debt Instrument, Term	10 years
4.24% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 125,000		125,000
Debt Instrument, Interest Rate, Stated Percentage	4.24%	4.24%
Debt Instrument, Maturity Date	Jun. 25, 2025
Debt Instrument, Term	10 years
3.91% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 75,000		75,000
Debt Instrument, Interest Rate, Stated Percentage	3.91%	3.91%
Debt Instrument, Maturity Date	Jun. 25, 2029
Debt Instrument, Term	10 years
3.19% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 50,000	€ 50,000	0
Debt Instrument, Interest Rate, Stated Percentage	3.19%	3.19%
Debt Instrument, Maturity Date	Jan. 24, 2035
Debt Instrument, Term	15 years
1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 153,299	€ 125,000	140,197
Debt Instrument, Interest Rate, Stated Percentage	1.47%	1.47%
Debt Instrument, Maturity Date	Jun. 17, 2030
Debt Instrument, Term	15 years
1.30% Euro-Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 165,563	€ 135,000	$ 151,413
Debt Instrument, Interest Rate, Stated Percentage	1.30%	1.30%
Debt Instrument, Maturity Date	Nov. 06, 2034
Debt Instrument, Term	15 years

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Fair value of the amount outstanding under the credit facility.

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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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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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