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Note 2 - Business Combination - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands		5 Months Ended
	Jan. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Liabilities
Goodwill		$ 22,985	$ 0
Geneva Pipe Company, Inc [Member]
Assets
Cash and cash equivalents		691
Trade and other receivables		7,089
Inventories		5,673
Prepaid expenses and other		356
Property and equipment		9,096
Operating lease right-of-use assets		21,684
Intangible assets		11,165
Total assets acquired		55,754
Liabilities
Accounts payable		1,395
Accrued liabilities		1,189
Operating lease liabilities		20,454
Deferred income taxes		5,343
Other long-term liabilities		939
Total liabilities assumed		29,320
Goodwill		22,985
Total purchase consideration	$ 49,400	$ 49,419