Inventories Inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Finished goods	$ 39,243	$ 37,143
Parts and materials	9,542	8,323
Work in progress	2,121	1,355
Total inventories	$ 50,906	$ 46,821

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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.

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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.

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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

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-Name Staff Accounting Bulletin (SAB)

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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.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Name Accounting Standards Codification

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