For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Name Accounting Standards Codification
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Summary of business and significant accounting policies - Description of Business (Details) - segment	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments			3
Revenue from Contract with Customer Benchmark \| Product Concentration Risk \| Mobile Navigation Services
Concentration Risk [Line Items]
Concentration risk, percentage	5.00%	5.00%