Note 2 - Business Combination - Assets Acquired and Liabilities Assumed (Details) - Ameron Water Transmission Group, LLC [Member] $ in Thousands	Jul. 27, 2018 USD ($)
Cash and cash equivalents	$ 912
Trade and other receivables	8,887
Contract assets	12,018
Inventories	7,937
Prepaid expenses and other	3,777
Property and equipment	34,827
Other assets	320
Total assets acquired	68,678
Accounts payable	5,520
Accrued liabilities	1,599
Contract liabilities	123
Deferred income taxes	3,221
Total liabilities assumed	10,463
Bargain purchase gain	(20,080)
Total purchase consideration	$ 38,135

The amount of contract assets recognized as of the acquisition date.

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Amount of accrued liabilities, assumed at the acquisition date.

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Amount of contract liabilities, assumed at the acquisition date.

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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.

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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.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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