Debt (Debt Schedule) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Fair value of debt	$ 503,402	$ 504,528
Total debt, net of unamortized discounts	498,951	500,954
Borrowings under lines of credit and overdrafts	5,908	30,825
Less current maturities	(7,828)	(32,892)
Long-term debt	491,123	468,062
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Carrying amount of debt	386,625	363,300
Fair value of debt	387,628	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	102,960	101,598
Lines of Credit and Overdrafts [Member]
Debt Instrument [Line Items]
Fair value of debt	5,908	30,825
Borrowings under lines of credit and overdrafts	5,908	30,825
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Carrying amount of debt	5,138	5,413
Fair value of debt	5,614	5,902
Foreign Bank Borrowings [Member]
Debt Instrument [Line Items]
Carrying amount of debt	1,280	1,416
Fair value of debt	$ 1,292	$ 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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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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-Subparagraph (SX 210.5-02.22)
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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-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

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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- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
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