Goodwill and Other Intangible Assets Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill	$ 53,920	$ 61,164
Credo
Business Acquisition [Line Items]
Goodwill	50,046	57,290
Credo \| Patents
Business Acquisition [Line Items]
Finite-lived intangible assets, net	260
Water Resource Company
Business Acquisition [Line Items]
Goodwill	3,874	$ 3,874
Indefinite-lived intangible assets (excluding goodwill)	$ 1,681

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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