Warranties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Warranty accrual:
Balance, beginning of period	$ 8,469	$ 8,130	$ 7,352
Payments made	(4,134)	(3,978)	(4,096)
Provisions	3,601	4,317	4,874
Adjustments related to changes in estimates	0	0	0
Balance, end of period	7,936	8,469	8,130
Warranty expense	$ 3,601	$ 4,317	$ 4,874

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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Period Type:	duration

- Definition

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3,4))
-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

+ Details

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- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

+ References

+ Details

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- Definition

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard product warranties (including adjustments related to changes in estimates). Does not include any Increase or Decrease in the liability for accruals related to extended product warranties.

+ References

+ Details

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- Definition

Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

+ References

+ Details

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