Note 4 - Revenue Recognition (Tables)

6 Months Ended

Jul. 31, 2019

Notes Tables

Disaggregation of Revenue [Table Text Block]

	Three Months Ended July 31,										Six Months Ended July 31,
	2019					2018					2019					2018
	Sales		% to Total			Sales		% to Total			Sales		% to Total			Sales		% to Total
Products		5,860		16	%		2,578		8	%		10,757		18	%		5,007		8	%
Specialty Piping Systems and Coating
Revenue recognized under input method		15,451		42	%		9,807		30	%		24,238		40	%		20,909		34	%
Revenue recognized under output method		15,356		42	%		19,940		62	%		25,948		42	%		35,298		58	%
Total		36,667		100	%		32,325		100	%		60,943		100	%		61,214		100	%

Contract with Customer, Asset and Liability [Table Text Block]

	Contract Assets
Balance January 31, 2019	$	1,653
Costs and gross profit recognized during the period for uncompleted contracts from the prior period		(1,038	)
Costs and deferred gross profit incurred on uncompleted contracts not billed at the end of the current period		1,368
Closing Balance at April 30, 2019	$	1,983
Costs and gross profit recognized during the period for uncompleted contracts from the prior period		(1,509	)
Costs and deferred gross profit incurred on uncompleted contracts not billed at the end of the current period		3,000
Closing Balance at July 31, 2019	$	3,474

	Contract Liabilities
Balance January 31, 2019	$	1,569
Revenue recognized during the period for uncompleted contracts from the prior period		(444	)
New contracts entered into that are uncompleted at the end of the current period		721
Closing Balance at April 30, 2019	$	1,846
Revenue recognized during the period for uncompleted contracts from the prior period		(1,250	)
New contracts entered into that are uncompleted at the end of the current period		545
Closing Balance at July 31, 2019	$	1,141