Goodwill, Long-lived Assets and Other Intangibles Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Goodwill [Line Items]
Goodwill impairment loss	$ 0	$ 0	$ 0	$ 0
Long-lived asset impairment loss	0	87	259	87
Goodwill [Roll Forward]
Goodwill Beginning balance			40,649	40,672
Goodwill, Acquired During Period			5,941
Goodwill, Written off Related to Sale of Business Unit			(52)
Goodwill, Foreign Currency Translation Gain (Loss)			214	31
Goodwill Ending balance	46,752	40,703	46,752	40,703
Applied Technology [Member]
Goodwill [Roll Forward]
Goodwill Beginning balance			12,342	12,365
Goodwill, Acquired During Period			0
Goodwill, Written off Related to Sale of Business Unit			0
Goodwill, Foreign Currency Translation Gain (Loss)			214	31
Goodwill Ending balance	12,556	12,396	12,556	12,396
Engineered Films [Member]
Goodwill [Roll Forward]
Goodwill Beginning balance			27,518	27,518
Goodwill, Acquired During Period			5,941
Goodwill, Written off Related to Sale of Business Unit			0
Goodwill, Foreign Currency Translation Gain (Loss)			0	0
Goodwill Ending balance	33,459	27,518	33,459	27,518
Aerostar [Member]
Goodwill [Line Items]
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount		$ 9,000		$ 9,000
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount		30.00%		30.00%
Goodwill [Roll Forward]
Goodwill Beginning balance			789	$ 789
Goodwill, Acquired During Period			0
Goodwill, Written off Related to Sale of Business Unit			(52)
Goodwill, Foreign Currency Translation Gain (Loss)			0	0
Goodwill Ending balance	$ 737	$ 789	$ 737	$ 789