Debt and Commitments (Details 1) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Oct. 15, 2014
Debt Instrument [Line Items]
Debt, Carrying Value	$ 2,115	$ 7,724
Finance lease, Carrying Amount	8,268	6,266
Finance lease, Fair Amount	8,650	6,515
Carrying Amount	704,259	834,775
Fair Value	722,109	856,616
Less current maturities	(4,391)	(9,758)
Long-term debt	699,868	825,017
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Debt, Carrying Amount	593,622	720,379
Debt, Fair Value	601,936	737,816
Senior Notes [Member] \| 3.97% Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Carrying Amount	100,000	100,000
Debt, Fair Value	$ 109,151	104,151
Interest rate	3.97%		3.97%
Lines of credit and overdrafts [Member]
Debt Instrument [Line Items]
Debt, Carrying Value	$ 2,115	7,724
Debt, Fair Value	2,115	7,724
Foreign bank borrowings [Member]
Debt Instrument [Line Items]
Debt, Carrying Amount	254	406
Debt, Fair Value	$ 257	$ 410

Debt and Lease Obligation, Fair Value Disclosure

No definition available.

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- Definition

Finance Lease Liability, Fair Value Disclosure

+ References

No definition available.

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- Definition

Long-term Debt and Lease Obligation, Excluding Current Maturities

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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