Business segment (Tables)

6 Months Ended

Jul. 31, 2016

Business segment reporting [Abstract]

Business segment reporting [Table Text Block]

	Three Months Ended July 31,						Six Months Ended July 31,
	2016			2015			2016			2015
Net sales
Piping Systems		$22,859			$25,147			$45,928			$45,424
Gross profit
Piping Systems		$2,980			$3,126			$4,972			$5,481
Loss from operations
Piping Systems		($714	)		($825	)		($2,415	)		($2,251	)
Corporate		($1,126	)		($1,705	)	(3,930		)	(3,849		)
Total loss from operations		($1,840	)		($2,530	)		($6,345	)		($6,100	)