Inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Finished goods	$ 35,743us-gaap_InventoryFinishedGoods	$ 32,249us-gaap_InventoryFinishedGoods
Parts and materials	10,888	9,147
Work in progress	2,538us-gaap_InventoryWorkInProcess	1,975us-gaap_InventoryWorkInProcess
Total inventories	$ 49,169us-gaap_InventoryNet	$ 43,371us-gaap_InventoryNet

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.6(a)(1))

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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-Publisher FASB

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-Topic 330

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of items purchased for use as components of a finished product or pieces of machinery and equipment plus any items in their natural and unrefined state. This element may be used when the reporting entity combines raw materials and purchased parts into an aggregate amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

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-Subparagraph (SX 210.5-02.6(a))

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-Publisher SEC

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-Number 210

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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-Name Accounting Standards Codification

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