CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income	Total
Balance at Jul. 31, 2018	$ 472	$ 330,770	$ (252,221)	$ 2,100	$ 81,121
Balance (in Shares) at Jul. 31, 2018	47,182,254
Net income (loss)			7,876		7,876
Exercise of stock options	$ 1	166			167
Exercise of stock options (in Shares)	34,719
Issuance of common stock for options exercised by Directors (in Shares)	23,376
Share-based compensation charges		725			725
Vesting of restricted stock (in Shares)	986
Issuance of common stock for employee 401(k) plan match	$ 3	829			832
Issuance of common stock for employee 401(k) plan match (in Shares)	315,472
Foreign currency translation adjustments				278	278
Balance at Apr. 30, 2019	$ 476	332,490	(244,345)	2,378	90,999
Balance (in Shares) at Apr. 30, 2019	47,556,807
Balance at Jan. 31, 2019	$ 472	331,463	(266,610)	2,172	67,497
Balance (in Shares) at Jan. 31, 2019	47,241,335
Net income (loss)			22,265		22,265
Exercise of stock options	$ 1	72			73
Issuance of common stock for options exercised by Directors		(73)			(73)
Share-based compensation charges		199			199
Issuance of common stock for employee 401(k) plan match	$ 3	829			832
Issuance of common stock for employee 401(k) plan match (in Shares)	315,472
Foreign currency translation adjustments				206	206
Balance at Apr. 30, 2019	$ 476	332,490	(244,345)	2,378	90,999
Balance (in Shares) at Apr. 30, 2019	47,556,807
Balance at Jul. 31, 2019	$ 476	332,704	(249,732)	2,580	86,028
Balance (in Shares) at Jul. 31, 2019	47,556,807
Net income (loss)			(25,195)		(25,195)
Share-based compensation charges		728			728
Vesting of restricted stock (in Shares)	811
Issuance of common stock for employee 401(k) plan match	$ 3	836			839
Issuance of common stock for employee 401(k) plan match (in Shares)	333,265
Foreign currency translation adjustments				(70)	(70)
Balance at Apr. 30, 2020	$ 479	334,268	(274,927)	2,510	62,330
Balance (in Shares) at Apr. 30, 2020	47,890,883
Balance at Jan. 31, 2020	$ 476	333,225	(265,067)	2,226	70,860
Balance (in Shares) at Jan. 31, 2020	47,557,618
Net income (loss)			(9,860)		(9,860)
Share-based compensation charges		209			209
Issuance of common stock for employee 401(k) plan match	$ 3	834			837
Issuance of common stock for employee 401(k) plan match (in Shares)	333,265
Foreign currency translation adjustments				284	284
Balance at Apr. 30, 2020	$ 479	$ 334,268	$ (274,927)	$ 2,510	$ 62,330
Balance (in Shares) at Apr. 30, 2020	47,890,883