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Note 3 - Business Combination (Details Textual) - Ameron Water Transmission Group, LLC [Member] - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 27, 2018 | Dec. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2018
Business Acquisition, Percentage of Voting Interests Acquired | 100.00% |  |  |
Business Combination, Consideration Transferred, Total | $ 38,135 |  |  |
Business Combination, Bargain Purchase, Increase (Decrease) in Gain Recognized, Measurement Period Adjustment |  | $ (1,800) |  |
Business Acquisition, Increase (Decrease) in Inventories, Measurement Period Adjustment |  | $ (2,000) |  |
Business Combination, Acquisition Related Costs |  |  |  | $ 2,600
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual |  |  | $ 30,200 |

X
- Definition The increase (decrease) during the reporting period for business acquisition due to measurement period adjustment in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities. + References No definition available. + Details
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Balance Type: | credit
Period Type: | duration

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 Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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X
- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6613-128477 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 (b) -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 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6578-128477 + Details
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- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Details
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