v3.26.1
DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
segment
Jun. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
Noncontrolling Interest [Line Items]          
Money market fund accounts included in cash equivalents | $ $ 33.4   $ 33.4   $ 33.9
Interest income | $ $ 0.4 $ 1.2 $ 0.8 $ 2.4  
Number of operating segments | segment     1    
Number of reportable segments | segment     1    
Brilliant Earth, LLC          
Noncontrolling Interest [Line Items]          
Noncontrolling interest, ownership percentage 83.40%   83.40%