Segment Reporting (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended	9 Months Ended
		Oct. 31, 2015	Oct. 31, 2014	Jul. 31, 2015	Oct. 31, 2015	Oct. 31, 2014
Segment Reporting Information [Line Items]
Net sales		$ 67,611	$ 91,292		$ 205,402	$ 288,287
Operating income		(2,727)	10,159		10,916	37,387
Administrative and general expenses		(3,802)	(4,935)		(13,322)	(15,690)
Goodwill impairment loss		7,413	0		7,413	0
Applied Technology Division [Member]
Segment Reporting Information [Line Items]
Net sales		21,344	33,161		74,165	115,696
Operating income	[1]	3,299	6,447		16,081	31,132
Gain (Loss) on Disposition of Assets		0			(611)
Engineered Films [Member]
Segment Reporting Information [Line Items]
Net sales		36,919	41,249		104,029	125,755
Operating income		6,145	5,486		15,981	17,165
Goodwill impairment loss		0	0		0	0
Aerostar Division [Member]
Segment Reporting Information [Line Items]
Net sales		9,456	19,257		27,338	56,179
Operating income		(8,378)	3,027		(7,917)	4,666
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	[2]	(108)	(2,375)		(130)	(9,343)
Operating income	[2]	9	134		93	114
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Operating income		1,075	15,094		24,238	53,077
Vista Reporting Unit [Member]
Segment Reporting Information [Line Items]
Goodwill impairment loss		7,413	$ 0		7,413	$ 0
Cost of Sales [Member] | Vista Research [Member]
Segment Reporting Information [Line Items]
Pre-contract deferred costs written off		2,933		$ 2,075	$ 2,933
Pre-contract costs deferred to inventory		858
Reduction in fair value of contingent consideration liability		$ 1,483

[1] (b) Includes gains of $611 for the nine-month period ended October 31, 2015 on disposal of assets related to the exit of contract manufacturing operations.

[2] (a) Fiscal 2016 intersegment sales were primarily sales from Engineered Films to Aerostar. Fiscal 2015 intersegment sales were comprised primarily of contract manufacturing sales from Aerostar to Applied Technology.