Preferred Stock and Common Stock - Schedule of Authorized, Issued and Outstanding Shares for Each Classes of Common Stock (Details) - shares	Sep. 30, 2025	Dec. 31, 2024
Class of Stock [Line Items]
Shares authorized (in shares)	13,850,000,000	13,850,000,000
Shares issued (in shares)	558,603,659	513,143,108
Shares outstanding (in shares)	558,603,659	513,143,108
Class A common stock
Class of Stock [Line Items]
Shares authorized (in shares)	12,500,000,000	12,500,000,000
Shares issued (in shares)	548,481,226	501,384,321
Shares outstanding (in shares)	548,481,226	501,384,321
Class B common stock
Class of Stock [Line Items]
Shares authorized (in shares)	1,250,000,000	1,250,000,000
Shares issued (in shares)	0	0
Shares outstanding (in shares)	0	0
Class C common stock
Class of Stock [Line Items]
Shares authorized (in shares)	100,000,000	100,000,000
Shares issued (in shares)	10,122,433	11,758,787
Shares outstanding (in shares)	10,122,433	11,758,787

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

Compass, Inc. 10-Q