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Summary of significant accounting policies - Additional Information (Details)
6 Months Ended
Oct. 14, 2021
Jun. 30, 2022
Customer
Jun. 30, 2021
Customer
Financing Receivable Impaired [Line Items]      
Reverse stock split 1-for-6.046    
Reverse stock split ratio 0.165    
Number of customer accounted for accounts receivable or revenue   0 0