Accrued Product Warranties (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrued product warranties, beginning of year	$ 18,499	$ 19,530	$ 18,051	$ 20,845
Amounts paid for warranty services	(4,332)	(3,790)	(12,809)	(12,781)
Warranty provisions for products sold	4,971	3,294	13,873	10,785
Currency translation adjustments and other	19	90	42	275
Accrued product warranties, end of year	19,157	19,124	19,157	19,124
Current accrued product warranties, end of year	15,567	16,193	15,567	16,193	$ 15,024
Long-term accrued product warranties, end of ear	$ 3,590	$ 2,931	$ 3,590	$ 2,931

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

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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Amount of foreign currency translation gain (loss) which decreases (increases) the standard and extended product warranty accrual.

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