Accounts And Other Receivables (Schedule Of Reconciliation Of The Beginning And Ending Balances Of The Allowance For Doubtful Accounts And Sales Returns) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts and other receivables, allowance for doubtful accounts and sales returns	$ 2,797	$ 1,904
Customer receivables	89,124	91,021
Allowance For Doubtful Accounts
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of year	1,904	2,054	$ 2,227
Charges to expense	1,901	715	450
Recoveries	(90)	(38)	(85)
Write-offs and settlements	(709)	(756)	(414)
Foreign exchange and other	(209)	(71)	(124)
Balance, end of year	$ 2,797	$ 1,904	$ 2,054

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) in valuation and qualifying accounts and reserves from adjustment.

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Amount of valuation and qualifying accounts and reserves.

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Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Amount of decrease in valuation and qualifying accounts and reserves.

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Amount of increase in valuation and qualifying accounts and reserves from recovery of amount previously written off or reestablishment of reserve previously utilized.

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