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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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The carrying value as of the balance sheet date of the current and noncurrent portions 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 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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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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Amount, after tax, of reclassification from accumulated other comprehensive income (AOCI) of gain (loss) from increase (decrease) in fair value of net investment hedge.

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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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Debt (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 323,585	$ 207,785	$ 126,480	$ 178,110
Debt Instrument, Covenant Compliance	The Company was in compliance with its debt covenants at March 31, 2020.
Senior Notes	$ 762,365
Unamortized Debt Issuance Expense	(2,232)
Debt, Long-term and Short-term, Combined Amount	1,569,418
Short-term borrowings and current maturities of long-term debt	(56,398)	(55,868)
Long-term Debt, Excluding Current Maturities	1,513,020	1,235,350
Gain (Loss) on Derivative Used in Net Investment Hedge, after Tax	2,000	$ 2,300
Cumulative (gain) loss in other other comprehensive income related to the change in a net investment hedge.	500
3.67 % Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	50,000
Debt Instrument, Face Amount	$ 50,000
Debt Instrument, Maturity Date	Dec. 17, 2022
Debt Instrument, Interest Rate, Stated Percentage	3.67%
4.10% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 50,000
Debt Instrument, Face Amount	$ 50,000
Debt Instrument, Maturity Date	Sep. 19, 2023
Debt Instrument, Interest Rate, Stated Percentage	4.10%
3.84% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 125,000
Debt Instrument, Face Amount	$ 125,000
Debt Instrument, Maturity Date	Sep. 19, 2024
Debt Instrument, Interest Rate, Stated Percentage	3.84%
4.24% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 125,000
Debt Instrument, Face Amount	$ 125,000
Debt Instrument, Maturity Date	Jun. 25, 2025
Debt Instrument, Interest Rate, Stated Percentage	4.24%
3.91% $75 million senior notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 75,000
Debt Instrument, Maturity Date	Jun. 25, 2029
Debt Instrument, Interest Rate, Stated Percentage	3.91%
3.91% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 75,000
Debt Instrument, Face Amount	$ 75,000,000
Debt Instrument, Maturity Date	Jun. 25, 2029
Debt Instrument, Interest Rate, Stated Percentage	3.91%
3.19% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 50,000
Debt Instrument, Face Amount	$ 50,000
Debt Instrument, Maturity Date	Jan. 24, 2035
Debt Instrument, Interest Rate, Stated Percentage	3.19%
1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 139,229
Debt Instrument, Face Amount	$ 125,000
Debt Instrument, Maturity Date	Jun. 17, 2030
Debt Instrument, Interest Rate, Stated Percentage	1.47%
1.30% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 150,368
Debt Instrument, Face Amount	$ 135,000
Debt Instrument, Maturity Date	Nov. 06, 2034
Debt Instrument, Interest Rate, Stated Percentage	1.30%
$1.1 Billion Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 342,900
Long-term Line of Credit	750,422
Debt Instrument, Face Amount	$ 1,100,000
Debt Instrument, Interest Rate, Stated Percentage	0.875%
Other Local Arrangements [Member]
Debt Instrument [Line Items]
Other Borrowings	$ 56,631
Swiss Pension Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8750.00%
Loan from Swiss Pension Plan USD Amount	$ 39,600
Swiss Pension Plan Loan in Swiss franc	38,000
Us Dollar Amounts Member
Debt Instrument [Line Items]
Senior Notes	473,894
Unamortized Debt Issuance Expense	(1,106)
Debt, Long-term and Short-term, Combined Amount	1,144,177
Short-term borrowings and current maturities of long-term debt	(1,053)
Long-term Debt, Excluding Current Maturities	1,143,124
Us Dollar Amounts Member \| 3.67 % Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	50,000
Us Dollar Amounts Member \| 4.10% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	50,000
Us Dollar Amounts Member \| 3.84% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	125,000
Us Dollar Amounts Member \| 4.24% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	125,000
Us Dollar Amounts Member \| 3.91% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	75,000
Us Dollar Amounts Member \| 3.19% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	50,000
Us Dollar Amounts Member \| 1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Us Dollar Amounts Member \| 1.30% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Us Dollar Amounts Member \| $1.1 Billion Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	668,997
Us Dollar Amounts Member \| Other Local Arrangements [Member]
Debt Instrument [Line Items]
Other Borrowings	1,286
Other Principal Trading Currencies [Member]
Debt Instrument [Line Items]
Senior Notes	288,471
Unamortized Debt Issuance Expense	(1,126)
Debt, Long-term and Short-term, Combined Amount	425,241
Short-term borrowings and current maturities of long-term debt	(55,345)
Long-term Debt, Excluding Current Maturities	369,896
Other Principal Trading Currencies [Member] \| 3.67 % Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Other Principal Trading Currencies [Member] \| 4.10% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Other Principal Trading Currencies [Member] \| 3.84% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Other Principal Trading Currencies [Member] \| 4.24% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Other Principal Trading Currencies [Member] \| 3.91% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Other Principal Trading Currencies [Member] \| 3.19% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	0
Other Principal Trading Currencies [Member] \| 1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	139,229
Other Principal Trading Currencies [Member] \| 1.30% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	150,368
Other Principal Trading Currencies [Member] \| $1.1 Billion Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	81,425
Other Principal Trading Currencies [Member] \| Other Local Arrangements [Member]
Debt Instrument [Line Items]
Other Borrowings	$ 55,345