Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Net income (loss) per share (Details) - shares	3 Months Ended		9 Months Ended
Net income (loss) per share (Details) - shares	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Unvested Restricted Stock [Member] \| In the Money Stock Options [Member]
Net income (loss) per share (Details) [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		431,000		694,000
Outstanding Options [Member] \| Out of the Money Stock Options [Member]
Net income (loss) per share (Details) [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,640,000	581,000	1,541,000	194,000