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
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Segment reporting - narrative (Details) - segment	6 Months Ended	12 Months Ended
Segment reporting - narrative (Details) - segment	Aug. 31, 2021	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2019
Segment Reporting [Abstract]
Number of reportable segments	2
Three Third-Party Payers \| Revenues \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk (as a percent)		33.00%	35.00%	35.00%