XML 11 R1.htm IDEA: XBRL DOCUMENT v3.25.2
Cover Page - shares
 6 Months Ended
Jun. 30, 2025
Aug. 11, 2025
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-42302  
Entity Registrant Name Chain Bridge Bancorp, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 20-4957796  
Entity Address, Address Line One 1445-A  
Entity Address, Address Line Two Laughlin Avenue  
Entity Address, City or Town McLean  
Entity Address, State or Province VA  
Entity Address, Postal Zip Code 22101  
City Area Code 703  
Local Phone Number 748-2005  
Title of 12(b) Security Class A common stock, par value $0.01 per share  
Trading Symbol CBNA  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period true  
Entity Shell Company false  
Entity Central Index Key 0001392272  
Current Fiscal Year End Date --12-31  
Amendment Flag false  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Class A Common Stock    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   3,151,496
Class B Common Stock    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   3,410,321