Debt (Debt Schedule) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Fair value of debt	$ 901,844	$ 942,276
Total debt, net of unamortized discounts	876,326	944,016
Borrowings under lines of credit and overdrafts	18,520	2,137
Less current maturities	(20,244)	(7,659)
Long-term debt	856,082	936,357
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Carrying amount of debt	752,035	831,016
Fair value of debt	771,523	828,800
Senior Notes [Member] \| 3.97% Senior Notes [Member]
Debt Instrument [Line Items]
Carrying amount of debt	100,000	100,000
Fair value of debt	105,793	100,185
Lines of Credit and Overdrafts [Member]
Debt Instrument [Line Items]
Fair value of debt	18,520	2,137
Borrowings under lines of credit and overdrafts	18,520	2,137
Finance Leases [Member]
Debt Instrument [Line Items]
Carrying amount of debt	5,323	10,216
Fair value of debt	5,556	10,503
Foreign Bank Borrowings [Member]
Debt Instrument [Line Items]
Carrying amount of debt	448	647
Fair value of debt	$ 452	$ 651

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.

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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.

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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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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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