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Note 20 - Quarterly Data (Unaudited) (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Jun. 30, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Goodwill, Impairment Loss |  |  |  | $ 5,282 | $ 16,066
Water Transmission Group [Member] |  |  |  |  |
Goodwill, Impairment Loss |  | $ 5,300 |  | 5,300 |
Denver Facility [Member] |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment | $ 7,900 |  | 7,860 |  |
Denver Facility [Member] | Water Transmission Group [Member] |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment | $ 7,900 |  | $ 7,900 |  |

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- Definition Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 + Details
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- Definition Amount of loss from the write-down of an asset representing the 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 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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