Debt (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Senior Notes	$ 489,567
Unamortized Debt Issuance Expense	(1,183)
Debt, Long-term and Short-term, Combined Amount	1,062,283
Short-term borrowings and current maturities of long-term debt	(53,798)	$ (49,670)
Long-term Debt, Excluding Current Maturities	1,008,485	985,021
Gain (Loss) on Derivative Used in Net Investment Hedge, after Tax	(2,300)	$ 5,500
Cumulative (gain) loss in other other comprehensive income related to the change in a net investment hedge.	$ (900)
Debt Instrument, Covenant Description	The note purchase agreement also requires the Company to maintain a consolidated interest coverage ratio of more than 3.5 to 1.0 and a consolidated leverage ratio of less than 3.5 to 1.0.
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%
1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	$ 140,750
Debt Instrument, Face Amount	$ 125,000
Debt Instrument, Maturity Date	Jun. 17, 2030
Debt Instrument, Interest Rate, Stated Percentage	1.47%
$1.1 Billion Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 575,200
Long-term Line of Credit	518,918
Debt Instrument, Face Amount	$ 1,100,000
Debt Instrument, Interest Rate, Stated Percentage	0.875%
3.91% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 75,000,000
Debt Instrument, Maturity Date	Jun. 25, 2029
Debt Instrument, Interest Rate, Stated Percentage	3.91%
Other Local Arrangements [Member]
Debt Instrument [Line Items]
Other Borrowings	$ 53,798
Swiss Pension Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	0.875%
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	349,138
Unamortized Debt Issuance Expense	(862)
Debt, Long-term and Short-term, Combined Amount	790,931
Short-term borrowings and current maturities of long-term debt	(1,261)
Long-term Debt, Excluding Current Maturities	789,670
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 \| 1.47% 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	440,532
Us Dollar Amounts Member \| Other Local Arrangements [Member]
Debt Instrument [Line Items]
Other Borrowings	1,261
Other Principal Trading Currencies [Member]
Debt Instrument [Line Items]
Senior Notes	140,429
Unamortized Debt Issuance Expense	(321)
Debt, Long-term and Short-term, Combined Amount	271,352
Short-term borrowings and current maturities of long-term debt	(52,537)
Long-term Debt, Excluding Current Maturities	218,815
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] \| 1.47% EURO Senior Notes [Member]
Debt Instrument [Line Items]
Senior Notes	140,750
Other Principal Trading Currencies [Member] \| $1.1 Billion Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	78,386
Other Principal Trading Currencies [Member] \| Other Local Arrangements [Member]
Debt Instrument [Line Items]
Other Borrowings	$ 52,537

Cumulative (gain) loss in other other comprehensive income related to the change in a net investment hedge.

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The loan value at the transaction date in US Dollar from two of the Company's non-U.S. pension plans issued at an arms length transaction to a wholly owned subsidiary of the Company which is classified as short-term.

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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any. Total may also include short-term borrowings, scheduled to be repaid within one year.

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The loan value at the transaction date in Swiss franc from two of the Company's non-U.S. pension plans issued at an arms length transaction to a wholly owned subsidiary of the Company which is classified as short-term.

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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

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- Definition

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 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 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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