Business segment (Tables)

3 Months Ended

Apr. 30, 2017

Segment Reporting [Abstract]

Business segment reporting [Table Text Block]

	Three Months Ended April 30,
	2017			2016
Net sales
Piping Systems		$23,501			$23,069
Gross profit
Piping Systems		$1,785			$1,992
Loss from operations
Piping Systems		($1,459	)		($1,701	)
Corporate		($2,358	)		($2,804	)
Total loss from operations		($3,817	)		($4,505	)