v3.26.1
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2026
Jul. 27, 2026
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity File Number 000-33063  
Entity Registrant Name SIERRA BANCORP  
Entity Incorporation, State or Country Code CA  
Entity Tax Identification Number 33-0937517  
Entity Address, Address Line One 86 North Main Street  
Entity Address, City or Town Porterville  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 93257  
City Area Code 559  
Local Phone Number 782-4900  
Title of 12(b) Security Common Stock, no par value  
Trading Symbol BSRR  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   12,963,397
Entity Central Index Key 0001130144  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q2  
Amendment Flag false