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Goodwil, Long-lived Assets, and Other Charges - Goodwill Narrative (Details)	12 Months Ended
	Jan. 31, 2019 USD ($) ReportingUnits	Jan. 31, 2018 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)
Goodwill [Line Items]
Number reporting units for Goodwill impairment analysis \| ReportingUnits	3
Goodwill	$ 50,942,000	$ 46,710,000	$ 40,649,000
Operating Income (Loss)
Goodwill [Line Items]
Goodwill impairment loss	0	0	0
Aerostar
Goodwill [Line Items]
Amount of estimated fair value that exceeded the net book value		$ 11,600,000		$ 9,000,000
Percentage of fair value in excess of carrying amount		41.00%		30.00%
Goodwill	634,000	$ 737,000	789,000	$ 789,000
Engineered Films
Goodwill [Line Items]
Goodwill	33,232,000	33,232,000	27,518,000
Applied Technology
Goodwill [Line Items]
Goodwill	$ 17,076,000	$ 12,741,000	$ 12,342,000