Stockholders' equity - Donations to Circle Foundation (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Mar. 31, 2025	Mar. 31, 2026
Class of Stock
Equity issuance cost		$ 7.7
Treasury Stock
Class of Stock
Re-issuance of treasury stock (in shares)		67,060
Class A common stock
Class of Stock
Shares approved for reservation (shares)	2,682,392
Shares approved for reservation as a percentage of capital stock (percent)	1.00%
Share approved for reservation exercise period (years)	10 years

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details