Net (Loss) / Income Per Share (“EPS”) - Computation of diluted EPS (Details) - shares	3 Months Ended
Oct. 31, 2018	Oct. 31, 2017
Accounting Policies [Abstract]
Weighted average number of common shares outstanding - Basic	22,806,777	22,430,121
Potentially dilutive common stock equivalents	31,892,421	32,088,399
Weighted average number of common and equivalent shares outstanding-Diluted	54,699,198	54,518,520

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 40
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1930-109256

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration