Summary of Significant Accounting Policies (Details Textuals 1) - customer	12 Months Ended
Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2019
Revenue Benchmark [Member]
Revenue, Major Customer [Line Items]
Concentration risk, benchmark description	more than 10	more than 10	more than 10
Concentration risk, customer	No single customer accounted for more than 10	No single customer accounted for more than 10
Number of Customers Exceeding Threshold	0	0	0
Accounts receivables
Revenue, Major Customer [Line Items]
Concentration risk, benchmark description	more than 10	more than 10
Concentration risk, customer	no customer accounted for more than 10%	no customer accounted for more than 10%
Number of Customers Exceeding Threshold	0	0

Identifies or describes the benchmark that serves as the denominator in the calculation of the percentage of concentration risk.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Balance Type:	na
Period Type:	duration