Summary of Significant Accounting Policies (Warranty and After-Sale Costs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Warranty and After-Sale Costs
Balance at beginning of year	$ 882us-gaap_StandardProductWarrantyAccrual	$ 881us-gaap_StandardProductWarrantyAccrual	$ 1,593us-gaap_StandardProductWarrantyAccrual
Net additions charged to earnings	2,512	1,005	719
Costs incurred and adjustments	(1,655)	(1,068)	(1,431)
Reserve acquired	0	64	0
Balance at end of year	1,739us-gaap_StandardProductWarrantyAccrual	882us-gaap_StandardProductWarrantyAccrual	881us-gaap_StandardProductWarrantyAccrual
Aquacue
Warranty and After-Sale Cost
Reserve acquired		$ 64

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- Definition

Total liability for standard and extended product warranties acquired in a business acquisition.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

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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

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)(1),(c)(5)

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Liability for a standard product warranty acquired in a business acquisition. Does not include any liability for an extended warranty acquired in a business acquisition.

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(2))

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Total increases or decreases in the standard product warranty liability for the period. Does not include increases or decreases in an extended warranty liability.

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