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Note 21 - Quarterly Data (Unaudited) (Details Textual) - USD ($) $ in Thousands |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 27, 2018 | Dec. 31, 2018 | Aug. 31, 2018 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Proceeds from Legal Settlements |  |  |  |  | $ 2,300 |  |  |  |  |  |
Gain (Loss) on Insurance Proceeds |  |  |  |  |  |  |  |  | $ 1,641 |  |
Business Combination, Bargain Purchase, Gain Recognized, Amount |  |  |  |  |  |  |  | $ 21,900 |  | $ 20,080 |
Ameron Water Transmission Group, LLC [Member] |  |  |  |  |  |  |  |  |  |  |
Business Combination, Bargain Purchase, Gain Recognized, Amount | $ 20,080 |  |  |  |  |  |  |  |  |  |
Business Combination, Bargain Purchase, Increase (Decrease) in Gain Recognized, Measurement Period Adjustment |  |  |  |  |  |  | $ (1,800) |  |  |  |
Property in Houston, Texas [Member] |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment, Total |  |  | $ 2,800 |  |  |  |  | $ 2,800 |  |  |
Monterrey, Mexico Facility [Member] |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment, Total |  | $ 200 |  |  |  |  | $ 200 |  |  |  |
Fire [Member] |  |  |  |  |  |  |  |  |  |  |
Production Related Impairments or Charges, Total |  |  |  | $ 2,700 | 700 | $ 3,200 |  |  |  |  |
Business Interruption Insurance Proceeds |  |  |  | 4,000 | 1,000 |  |  |  | 5,000 |  |
Gain (Loss) on Insurance Proceeds |  |  |  | $ 1,200 | $ 400 |  |  |  | $ 1,600 |  |

X
- Definition In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined) due to measurement period adjustment, this element represents the increase (decrease) amount of gain recognized by the entity. + References No definition available. + Details
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- Definition In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6571-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6387-128476 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6396-128476 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6527-128477 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6393-128476 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
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