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Note 3 - Business Combinations (Details Textual) $ in Thousands |  |  | 3 Months Ended | 11 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 31, 2020 USD ($) | Jul. 27, 2018 USD ($) | Jun. 30, 2020 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Number of Operating Segments | 1 |  |  |  |  | 1 |  |
Geneva Pipe Company, Inc. [Member] |  |  |  |  |  |  |  |
Business Acquisition, Percentage of Voting Interests Acquired | 100.00% |  |  |  |  |  |  |
Business Combination, Consideration Transferred, Total | $ 49,419 |  |  |  |  |  |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Trade and Other Receivables |  |  | $ (100) |  |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  |  |  | $ 2,600 | $ 600 |
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual |  |  |  |  | $ 44,200 |  |  |
Ameron Water Transmission Group, LLC [Member] |  |  |  |  |  |  |  |
Business Acquisition, Percentage of Voting Interests Acquired |  | 100.00% |  |  |  |  |  |
Business Combination, Consideration Transferred, Total |  | $ 38,135 |  |  |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  |  |  |  |  | $ 2,600
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, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred |  |  |  |  |  |  | $ 0 |

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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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 This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to trade and other receivables acquired in connection with a business combination for which the initial accounting was incomplete. + 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=116868678&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=116859721&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=120321790&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=116859721&loc=d3e6578-128477 + Details
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X
- Definition This element represents the amount of revenue 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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X
- Definition This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 4A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121647850&loc=SL65897772-128472 + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
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- Details
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