Revenue and Contract Receivables, net (Details) (USD $)	3 Months Ended										3 Months Ended					3 Months Ended
	Oct. 31, 2013		Oct. 31, 2012		Jul. 31, 2013	Oct. 31, 2013 United States, Canada and South America [Member]	Jul. 31, 2013 United States, Canada and South America [Member]	Oct. 31, 2013 Middle East, Africa [Member]	Jul. 31, 2013 Middle East, Africa [Member]	Oct. 31, 2012 Middle East, Africa [Member]	Oct. 31, 2013 Middle East, Africa Projects [Member]	Jan. 31, 2013 Middle East, Africa Projects [Member]	Oct. 31, 2012 Middle East, Africa Projects [Member]	Oct. 31, 2013 Asia [Member]	Jul. 31, 2013 Asia [Member]	Oct. 31, 2013 China	Oct. 31, 2012 China
Contracts Receivable [Line Items]
Billed Contracts Receivable	$ 25,671,439				$ 36,284,950
Unbilled Contracts Receivable	26,737,450				16,441,857
Contracts Receivable, Gross	52,408,889				52,726,807	41,352,521	41,302,180	10,716,881	10,876,151	3,400,000			20,300,000	339,487	548,476		4,700,000
Contract receivables (in hundredths)	21.00%				22.00%
Allowance for doubtful accounts receivables (in hundredths)	65.00%				72.00%
Allowance for doubtful accounts and contract adjustments	(5,639,291)		(11,322,000)			1,974,557	1,576,746	3,535,188	3,886,508					129,546	129,546		2,100,000
Total contract receivables, net	46,769,598				47,134,007
Contractual retainage balance included under billed contract receivable	0				0
Management anticipation for receivables collection	1 year
Cash received related to a project												7,100,000
Reduction in allowance for doubtful accounts and contract adjustments											1,700,000
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of period	5,592,800		10,238,391			(1,974,557)	(1,576,746)	(3,535,188)	(3,886,508)			(7,400,000)		(129,546)	(129,546)		(2,100,000)
Net increase (decrease) due to adjustments in the allowance for contract adjustments (1)	22,228	[1]	1,072,591	[1]												1,000,000
Net increase (decrease) due to adjustments in the allowance for doubtful accounts (2)	24,263	[2]	11,018	[2]
Balance at end of period	$ 5,639,291		$ 11,322,000			$ (1,974,557)	$ (1,576,746)	$ (3,535,188)	$ (3,886,508)					$ (129,546)	$ (129,546)		$ (2,100,000)

[1] Increases (decreases) to the allowance for contract adjustments on the consolidated balance sheets are also recorded as (decreases) increases to revenue on the consolidated statements of operations.

[2] Increases (decreases) to the allowance for doubtful accounts on the consolidated balance sheets are also recorded as increases (decreases) to administrative and other indirect operating expenses on the consolidated statements of operations.