v3.26.1
Net Income Per Share - Schedule of Reconciliations of the Numerators and Denominators Used to Compute Basic and Diluted (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Earnings Per Share [Abstract]        
Net income attributable to Black Rock Coffee Bar, Inc. $ 1,218 $ 0 $ 1,596 $ 0
Weighted-average number of shares of Class A common stock outstanding (in shares) 21,216,632   19,399,560  
Basic net income per share attributable to Class A common shareholders (in dollars per share) $ 0.06   $ 0.08  
Diluted net income attributable to Black Rock Coffee Bar, Inc. $ 1,218   $ 1,596  
Add: Weighted-average effect of dilutive securities RSUs 2,750   1,375  
Weighted-average number of shares of Class A common stock outstanding used to calculate diluted net income per share (in shares) 21,219,382   19,400,935  
Diluted net income per share attributable to Class A common shareholders (in dollars per share) $ 0.06   $ 0.08