Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
Segment Reporting Information [Line Items]
Net sales	$ 112,486	$ 86,496
Operating income	11,573	3,939
Applied Technology [Member]
Segment Reporting Information [Line Items]
Net sales	54,868	42,007
Operating income	13,187	8,939
Engineered Films [Member]
Segment Reporting Information [Line Items]
Net sales	48,765	33,398
Operating income	6,767	1,607
Aerostar [Member]
Segment Reporting Information [Line Items]
Net sales	8,887	11,151
Operating income	589	293
Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(34)	(60)
Operating income	(7)	40
Reportable Segments
Segment Reporting Information [Line Items]
Net sales	112,486	86,496
Operating income	20,536	10,879
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Administrative and general expenses	$ (8,963)	$ (6,940)