Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Income (loss) from continuing operations before provision (benefit) for income taxes and noncontrolling interest [Abstract]
Domestic	$ 5,432	$ 4,558	$ 3,500
Foreign	(7)	(191)	4,469
Income before income tax provision	5,425	4,367	7,969
Current [Abstract]
Federal	(149)	1,155	488
State	42	177	80
Foreign	655	730	2,047
Total current	548	2,062	2,615
Deferred [Abstract]
Federal	2,075	587	1,379
State	308	269	172
Foreign	(459)	841	(397)
Total deferred	1,924	1,697	1,154
Total income tax provision	2,472	3,759	3,769
Reconciliation of income tax provision from statutory U.S. income tax rate to the effective income tax rate [Abstract]
Income tax provision at the U.S. federal statutory income tax rate	1,845	1,485	2,709
Foreign dividend income	240	263	508
State taxes, net of federal benefit	200	312	166
Other permanent differences	54	88	209
Peru non-deductible expenses	53	59	167
Other foreign taxes, net of federal benefit	14	153	161
International rate differences	2	(145)	(338)
Income from "pass-through" entities taxable to noncontrolling partners	(1)	(39)	31
Re-evaluation and settlements of tax contingencies	(33)	0	0
Total income tax provision	2,472	3,759	3,769
Unrecognized tax benefits, income tax penalties and interest expense [Abstract]
Unrecognized tax benefits, income tax penalties and interest expense	100
Deferred tax assets [Abstract]
Contract and other reserves						$ 520	$ 3,023
Accrued compensation and expenses						752	734
Net operating loss carryforwards						1,470	1,265
Foreign and state income taxes						17	59
Foreign tax credit						296	296
Federal benefit from foreign tax audits						0	157
Other						714	(26)
Deferred tax assets						3,769	5,508
Less: Valuation allowance	(2,278)	(2,278)	(560)			(2,020)	(2,278)	$ (560)
Net deferred tax assets						1,749	3,230
Deferred tax liabilities [Abstract]
Federal expense on state deferred taxes						(73)	(133)
Fixed assets and intangibles						(144)	(759)
Federal expense from foreign accounting differences						(332)	(213)
Net deferred tax liabilities						(549)	(1,105)
Amount of undistributed income that will not be indefinitely reinvested in foreign operations						300	100	0
Amount of undistributed income indefinitely reinvested in foreign operations						7,100
Deferred tax assets valuation allowance [Abstract]
Balance at beginning of period	2,278	560
Additions during the period	2	1,765
Reductions during period	(260)	(47)
Balance at end of period	2,020	2,278	560
Domestic operating income (losses)	(800)
Gross unrecognized tax benefits that would impact effective tax rate in future periods						$ 300	$ 100	$ 100
Maximum [Member]
Unrecognized tax benefits, income tax penalties and interest expense [Abstract]
Unrecognized tax benefits, income tax penalties and interest expense		100	100
Canada And China [Member]
Reconciliation of income tax provision from statutory U.S. income tax rate to the effective income tax rate [Abstract]
Valuation allowance	(39)	1	156
Brazil [Member]
Reconciliation of income tax provision from statutory U.S. income tax rate to the effective income tax rate [Abstract]
Valuation allowance	$ 137	$ 1,582	$ 0
IRS [Member]
Income Tax Examination [Line Items]
Income tax examination, year subject to examination	2017	2016	2015	2014
State, Local and Foreign [Member]
Income Tax Examination [Line Items]
Income tax examination, year subject to examination	2017	2016	2015	2014	2013