Debt (Debt Schedule) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Carrying amount of debt	$ 5,341	$ 7,724
Carrying amount of finance leases	5,531	6,266
Fair value of finance leases	5,656	6,515
Carrying amount of debt and finance leases	718,509	834,775
Fair value of debt and finance leases	730,121	856,616
Less current maturities	(7,152)	(9,758)
Long-term debt	711,357	825,017
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Carrying amount of debt	607,318	720,379
Fair value of debt	608,781	737,816
Senior Notes [Member] \| 3.97% Senior Notes [Member]
Debt Instrument [Line Items]
Carrying amount of debt	100,000	100,000
Fair value of debt	110,024	104,151
Lines of Credit and Overdrafts [Member]
Debt Instrument [Line Items]
Carrying amount of debt	5,341	7,724
Fair value of debt	5,341	7,724
Foreign Bank Borrowings [Member]
Debt Instrument [Line Items]
Carrying amount of debt	319	406
Fair value of debt	$ 319	$ 410

Debt and Lease Obligation, Fair Value Disclosure

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- Definition

Finance Lease Liability, Fair Value Disclosure

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- Definition

Long-term Debt and Lease Obligation, Excluding Current Maturities

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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.

+ References

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

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
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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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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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-Subparagraph (b)
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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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- 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.

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-Publisher FASB
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