Debt (Debt Schedule) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Oct. 31, 2014
Debt Instrument [Line Items]
Carrying amount of debt	$ 7,507	$ 2,115
Carrying amount of finance leases	7,343	8,268
Fair value of finance leases	8,508	8,650
Carrying amount of debt and finance leases	673,573	704,259
Fair value of debt and finance leases	721,952	722,109
Less current maturities	(9,558)	(4,391)
Long-term debt	664,015	699,868
Amended Credit Agreement
Debt Instrument [Line Items]
Carrying amount of debt		593,622
Fair value of debt	596,456	601,936
Senior Notes \| 3.97% Senior Notes
Debt Instrument [Line Items]
Carrying amount of debt	100,000	100,000
Fair value of debt	$ 109,282	109,151
Stated interest rate	3.97%		3.97%
Lines of Credit and Overdrafts
Debt Instrument [Line Items]
Carrying amount of debt	$ 7,507	2,115
Fair value of debt	7,507	2,115
Other foreign bank borrowings
Debt Instrument [Line Items]
Carrying amount of debt	197	254
Fair value of debt	$ 199	$ 257

Debt and Lease Obligation, Fair Value Disclosure

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Finance Lease Liability, Fair Value Disclosure

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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.

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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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-Publisher FASB
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Contractual interest rate for funds borrowed, under the debt agreement.

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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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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
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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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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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