v3.26.1
Organization, Description of Business and Summary of Significant Accounting Policies (Details)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended
Jan. 31, 2026
USD ($)
Jun. 30, 2025
USD ($)
$ / shares
shares
Mar. 31, 2026
client
issuer
$ / shares
shares
Mar. 31, 2025
client
Summary of Significant Accounting Policies        
Number of issuers of credit card receivable | issuer     2  
Common stock, shares outstanding, after reorganization   64,060,082    
Shares repurchased | $ $ 58.9      
Purchased Receivables | Purchase concentration | Top five clients        
Summary of Significant Accounting Policies        
Number of major suppliers | client     5 5
Concentration risk percentage     41.30% 53.40%
Purchased Receivables | Purchase concentration | Top client        
Summary of Significant Accounting Policies        
Concentration risk percentage     9.20% 17.00%
Class B units        
Summary of Significant Accounting Policies        
Vesting period   3 years    
JCAP TopCo, LLC [Member] | Class A And Class C Units        
Summary of Significant Accounting Policies        
Number of units outstanding     132,828,019  
JCAP TopCo, LLC [Member] | Class B units        
Summary of Significant Accounting Policies        
Number of units outstanding   27,937,232    
IPO        
Summary of Significant Accounting Policies        
Offering price | $ / shares   $ 15 $ 15  
Net proceeds | $   $ 4.5    
Shares issued (in shares)   625,000    
Sale of Stock, Number of Shares Issued in Transaction   10,875,000    
JCAP TopCo, LLC [Member]        
Summary of Significant Accounting Policies        
Exchange ratio of stock     2.4150549  
JCAP TopCo, LLC [Member] | Class A And Class C Units        
Summary of Significant Accounting Policies        
Shares Issued, Conversion of stock     55,000,000  
JCAP TopCo, LLC [Member] | Class B units        
Summary of Significant Accounting Policies        
Shares Issued, Conversion of stock   9,060,082    
JCAP TopCo, LLC [Member] | Class B units | Management Stockholders        
Summary of Significant Accounting Policies        
Shares Issued, Conversion of stock   6,418,775    
Jefferson Capital Holdings, LLC | J C Flowers        
Summary of Significant Accounting Policies        
Ownership percentage 53.10%   67.60%  
Jefferson Capital Holdings, LLC | Management Stockholders        
Summary of Significant Accounting Policies        
Ownership percentage, Noncontrolling owner     14.50%  
Jefferson Capital Holdings, LLC | IPO | Investors        
Summary of Significant Accounting Policies        
Ownership percentage, Noncontrolling owner     32.40%  
Jefferson Capital Holdings, LLC | JCAP TopCo, LLC [Member]        
Summary of Significant Accounting Policies        
Ownership percentage   100.00%    
JCAP TopCo, LLC [Member]        
Summary of Significant Accounting Policies        
Ownership percentage   100.00%