Revenue Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Disaggregation of Revenue [Line Items]
Net sales	$ 114,426	$ 85,179	$ 226,912	$ 171,675
Applied Technology [Member]
Disaggregation of Revenue [Line Items]
Net sales	44,601	35,502	99,469	77,509
Aerostar [Member]
Disaggregation of Revenue [Line Items]
Net sales	12,787	13,465	21,674	24,616
Engineered Films [Member]
Disaggregation of Revenue [Line Items]
Net sales	57,087	36,252	105,852	69,650
All Segments [Member]
Disaggregation of Revenue [Line Items]
Net sales	114,426	85,179	226,912	171,675
UNITED STATES | Lighter-than-air [Member]
Disaggregation of Revenue [Line Items]
Net sales	9,479	10,008	13,978	16,090
UNITED STATES | Plastic Films and Sheeting [Member]
Disaggregation of Revenue [Line Items]
Net sales	52,288	32,440	97,656	62,936
UNITED STATES | Precision Agriculture [Member]
Disaggregation of Revenue [Line Items]
Net sales	32,209	27,998	67,861	58,859
UNITED STATES | Other Product [Member]
Disaggregation of Revenue [Line Items]
Net sales	3,306	3,423	7,073	8,475
UNITED STATES | Applied Technology [Member] | Precision Agriculture [Member]
Disaggregation of Revenue [Line Items]
Net sales	32,209	28,000	67,861	58,861
UNITED STATES | Aerostar [Member] | Lighter-than-air [Member]
Disaggregation of Revenue [Line Items]
Net sales	9,479	10,008	13,978	16,090
UNITED STATES | Aerostar [Member] | Other Product [Member]
Disaggregation of Revenue [Line Items]
Net sales	3,306	3,423	7,073	8,475
UNITED STATES | Engineered Films [Member] | Plastic Films and Sheeting [Member]
Disaggregation of Revenue [Line Items]
Net sales	52,337	32,478	97,739	63,034
Non-US [Member] | Lighter-than-air [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	34	597	46
Non-US [Member] | Plastic Films and Sheeting [Member]
Disaggregation of Revenue [Line Items]
Net sales	4,750	3,774	8,113	6,616
Non-US [Member] | Precision Agriculture [Member]
Disaggregation of Revenue [Line Items]
Net sales	12,392	7,502	31,608	18,648
Non-US [Member] | Other Product [Member]
Disaggregation of Revenue [Line Items]
Net sales	2	0	26	5
Non-US [Member] | Applied Technology [Member] | Precision Agriculture [Member]
Disaggregation of Revenue [Line Items]
Net sales	12,392	7,502	31,608	18,648
Non-US [Member] | Aerostar [Member] | Lighter-than-air [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	34	597	46
Non-US [Member] | Aerostar [Member] | Other Product [Member]
Disaggregation of Revenue [Line Items]
Net sales	2	0	26	5
Non-US [Member] | Engineered Films [Member] | Plastic Films and Sheeting [Member]
Disaggregation of Revenue [Line Items]
Net sales	4,750	3,774	8,113	6,616
Consolidation, Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales	(49)	(40)	(83)	(100)
Consolidation, Eliminations [Member] | UNITED STATES | Plastic Films and Sheeting [Member]
Disaggregation of Revenue [Line Items]
Net sales	(49)	(38)	(83)	(98)
Consolidation, Eliminations [Member] | UNITED STATES | Precision Agriculture [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	(2)	0	(2)
Consolidation, Eliminations [Member] | Non-US [Member] | Plastic Films and Sheeting [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 0	$ 0	$ 0	$ 0