Consolidated Statements of Equity (Unaudited) - USD ($) $ in Thousands	Total	Additional Paid-in Capital [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Common Stock Class A [Member]	Common Stock Class B [Member]
BALANCE AT JULY 31, 2019 at Jul. 31, 2019	$ 53,557	$ 273,313	$ (51,739)	$ (4,858)	$ (160,763)	$ (2,687)	$ 33	$ 258
Stock-based compensation	3,341	3,339						2
Distributions to noncontrolling interests	(680)					(680)
Other comprehensive loss	(2,280)			(2,280)
Exercise of stock options	276	276
Repurchases of Class B common stock through repurchase program	(212)		(212)
Restricted Class B common stock purchased from employees	(266)		(266)
Net loss	(133)				(63)	(70)
BALANCE AT APRIL 30, 2020 at Apr. 30, 2020	53,603	276,928	(52,217)	(7,138)	(160,826)	(3,437)	33	260
BALANCE AT JULY 31, 2019 at Jan. 31, 2020	53,393	276,118	(52,005)	(6,575)	(161,344)	(3,094)	33	260
Stock-based compensation	810	810
Distributions to noncontrolling interests	(210)					(210)
Other comprehensive loss	(563)			(563)
Repurchases of Class B common stock through repurchase program	(212)		(212)
Net loss	385				518	(133)
BALANCE AT APRIL 30, 2020 at Apr. 30, 2020	53,603	276,928	(52,217)	(7,138)	(160,826)	(3,437)	33	260
BALANCE AT JULY 31, 2019 at Jul. 31, 2020	71,139	277,443	(56,221)	(7,410)	(139,333)	(3,633)	33	260
Business acquisition	1,920	(21)				1,941
Stock-based compensation	1,215	1,212						3
Distributions to noncontrolling interests	(646)					(646)
Other comprehensive loss	(980)			980
Exercise of stock options	686	686
Repurchases of Class B common stock through repurchase program	(2,849)		(2,849)
Restricted Class B common stock purchased from employees	(1,343)		(1,343)
Grant of restricted equity in subsidiary (see Note 11).		(2,195)				2,195
Net loss	58,018				57,744	274
BALANCE AT APRIL 30, 2020 at Apr. 30, 2021	127,160	277,125	(60,413)	(8,390)	(81,589)	131	33	263
BALANCE AT JULY 31, 2019 at Jan. 31, 2021	90,416	276,871	(60,413)	(8,957)	(117,937)	556	33	263
Business acquisition	(268)	(21)				(247)
Stock-based compensation	275	275
Distributions to noncontrolling interests	(228)					228
Other comprehensive loss	567			567
Repurchases of Class B common stock through repurchase program
Net loss	36,398				36,348	50
BALANCE AT APRIL 30, 2020 at Apr. 30, 2021	$ 127,160	$ 277,125	$ (60,413)	$ (8,390)	$ (81,589)	$ 131	$ 33	$ 263