Environmental Costs (Schedule of Change in Environmental Remediation) (Details) - Accruals and Payable and Other Long Term Liabilities - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Accrual for Environmental Loss Contingencies [Roll Forward]
Balance at January 1	$ 6,078	$ 5,531
Net additions to accrual	141	1,122
Payments	(165)	(569)
Changes in foreign currency exchange rates	(5)	(6)
Balance at December 31	$ 6,049	$ 6,078

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

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Amount of foreign currency translation gain (loss) which decreases (increases) the accrual for environmental loss contingencies.

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Amount of cash outflow to settle environmental loss contingencies.

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