Debt Debt Table (Details) € in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Rate	Dec. 31, 2019 EUR (€)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Debt Issuance Costs, Gross	$ 3,400
Senior Notes	714,351		$ 491,819
Debt issuance costs, net	(2,259)		(1,234)
Other Borrowings	55,868		49,670
Total debt	1,291,218		1,034,691
Less: current portion	(55,868)		(49,670)
Long-term debt	$ 1,235,350		985,021
Debt Instrument, Term	10 years
Debt Instrument, Basis Spread on Variable Rate \| Rate	87.50%
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, Term	10 years
Debt Instrument, Maturity Date	Sep. 19, 2023
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, Term	10 years
Debt Instrument, Maturity Date	Sep. 19, 2024
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, Term	10 years
Debt Instrument, Maturity Date	Jun. 25, 2025
3.91% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 75,000		0
Debt Instrument, Interest Rate, Stated Percentage	3.91%	3.91%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Jun. 25, 2029
1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 140,197	€ 125,000	143,053
Debt Instrument, Interest Rate, Stated Percentage	1.47%	1.47%
Debt Instrument, Term	15 years
Debt Instrument, Maturity Date	Jun. 17, 2030
1.30% Euro-Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 151,413	€ 135,000	0
Debt Instrument, Interest Rate, Stated Percentage	1.30%	1.30%
Debt Instrument, Term	15 years
Debt Instrument, Maturity Date	Nov. 06, 2034
Line of Credit [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Gross	$ 2,000
$1.1 billion Credit Agreement, interest at LIBOR plus 87.5 basis points(1)	$ 520,999		$ 493,202
Debt Instrument, Maturity Date	Jun. 15, 2023
Debt Instrument, Basis Spread on Variable Rate \| Rate	0.875%

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

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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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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Fair value of the amount outstanding under the credit 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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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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