Debt and Commitments (Details 1) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Borrowings under lines of credit and overdrafts	$ 7,724	$ 2,137
Finance lease, Carrying Amount	6,266
Finance lease, Fair Amount	6,515
Capital lease, Carry amount		10,216
Capital lease, Fair Amount		10,503
Carrying Amount	834,775	944,016
Fair Value	856,616	942,276
Less current maturities	(9,758)	(7,659)
Long-term debt	825,017	936,357
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Debt, Carrying Amount	720,379	831,016
Debt, Fair Value	737,816	828,800
Senior Notes [Member] \| 3.97% Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Carrying Amount	100,000	100,000
Debt, Fair Value	104,151	100,185
Lines of credit and overdrafts [Member]
Debt Instrument [Line Items]
Debt, Fair Value	7,724	2,137
Borrowings under lines of credit and overdrafts	7,724	2,137
Foreign bank borrowings [Member]
Debt Instrument [Line Items]
Debt, Carrying Amount	406	647
Debt, Fair Value	$ 410	$ 651

Capital Lease Obligation, Fair Value Disclosure

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Debt and Lease Obligation, Fair Value Disclosure

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Finance Lease Liability, Fair Value Disclosure

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Long-term Debt and Lease Obligation, Excluding Current Maturities

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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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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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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