Debt (Debt Schedule) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Fair value of debt	$ 537,579	$ 508,265
Total debt, net of unamortized discounts	527,471	509,906
Borrowings under lines of credit and overdrafts	13,200	22,680
Less current maturities	(15,411)	(24,195)
Long-term debt	512,060	485,711
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Carrying amount of debt	406,410	379,700
Fair value of debt	407,881	375,188
Senior Notes [Member] \| 3.97% Senior Notes [Member]
Debt Instrument [Line Items]
Carrying amount of debt	100,000	100,000
Fair value of debt	108,447	102,484
Borrowings Under Lines of Credit and Overdrafts [Member]
Debt Instrument [Line Items]
Fair value of debt	13,200	22,680
Borrowings under lines of credit and overdrafts	13,200	22,680
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Carrying amount of debt	6,175	7,105
Fair value of debt	6,398	7,503
Other Foreign Bank Borrowings [Member]
Debt Instrument [Line Items]
Carrying amount of debt	1,686	421
Fair value of debt	$ 1,653	$ 410

Total debt, net of unamortized discounts

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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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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond 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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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
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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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No definition available.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). 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 942
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-Number 210
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