v3.26.3
Summary of Significant Accounting Policies (Details)
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Summary of Significant Accounting Policies [Abstract]              
Number of reportable segments     1   1    
Number of operating segments     1   1    
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]     Chief Executive Officer   Chief Executive Officer    
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description     The CODM allocates resources and assesses performance based upon financial information at the entity-wide level. Since the CODM makes operating decisions and allocates resources on an entity-wide basis, Fold operates as one operating segment and one reportable segment.   The primary financial measure used by the CODM to evaluate performance is operating income (loss) as shown on the statements of operations. Segment expenses and other segment items are provided to the CODM on the same basis as disclosed in the statements of operations.    
Cash and cash equivalents $ 28,386,785 $ 6,609,719 $ 28,386,785 $ 6,609,719 $ 7,652,203 $ 18,330,359 $ 1,491,544
Federal deposit insurance corporation coverage         250,000    
Amortization expense on capitalized software development costs 200,000 100,000 $ 300,000 200,000 600,000 300,000  
Amortization expense write-offs       $ 100,000 $ 0  
Notional amount of customer rewards liability outstanding     77   79 92  
Derivative instruments within customer rewards liability 4,504,290   $ 4,504,290   $ 6,872,869 $ 8,569,651  
Gain (loss) on remeasurement of derivative liability $ 700,000 $ (2,100,000) $ 2,300,000 $ 1,000,000 800,000 (5,200,000)  
Marketing and advertising expense         $ 1,200,000 $ 300,000