Related party transactions (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Related party transactions
Royalties earned	$ 0
Consultancy services with Stone Sunny Isles Inc.
Related party transactions
Amount of transaction	$ 43,000,000	$ 40,000,000

Amount of transactions with related party during the financial reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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