XML 12 R1.htm IDEA: XBRL DOCUMENT v3.21.2
Document and Entity Information - shares
 6 Months Ended
Jun. 30, 2021
Sep. 16, 2021
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Transition Report false  
Document Period End Date Jun. 30, 2021  
Entity File Number 333-254200  
Entity Registrant Name CATALYST BANCORP, INC.  
Entity Incorporation, State or Country Code LA  
Entity Tax Identification Number 86-2411762  
Entity Address, Address Line One 235 N. Court Street  
Entity Address, City or Town Opelousas  
Entity Address State Or Province LA  
Entity Address, Postal Zip Code 70570  
City Area Code 337  
Local Phone Number 948-3033  
Title of 12(b) Security None  
No Trading Symbol Flag true  
Entity Current Reporting Status No  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   0
Entity Central Index Key 0001849867  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2021  
Document Fiscal Period Focus Q2  
Amendment Flag false