Debt (Debt Schedule) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Fair value of debt	$ 524,562	$ 504,528
Total debt, net of unamortized discounts	515,993	500,954
Borrowings under lines of credit and overdrafts	16,875	30,825
Less current maturities	(18,564)	(32,892)
Long-term debt	497,429	468,062
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Carrying amount of debt	393,000	363,300
Fair value of debt	397,805	364,775
Senior Notes [Member] \| 3.97% Senior Notes [Member]
Debt Instrument [Line Items]
Carrying amount of debt	100,000	100,000
Fair value of debt	103,319	101,598
Lines of Credit and Overdrafts [Member]
Debt Instrument [Line Items]
Fair value of debt	16,875	30,825
Borrowings under lines of credit and overdrafts	16,875	30,825
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Carrying amount of debt	4,882	5,413
Fair value of debt	5,314	5,902
Foreign Bank Borrowings [Member]
Debt Instrument [Line Items]
Carrying amount of debt	1,236	1,416
Fair value of debt	$ 1,249	$ 1,428

Total debt, net of unamortized discounts

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- Definition

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

+ References

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Subparagraph (a)
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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.

+ References

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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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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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