XML 12 R1.htm IDEA: XBRL DOCUMENT v3.19.1
Document and Entity Information - shares
 3 Months Ended
Mar. 31, 2019
May 03, 2019
Document and entity information [Abstract]    
Current fiscal year end date --12-31  
Entity central index key 0000750574  
Entity current reporting status Yes  
Entity filer category Accelerated Filer  
Entity registrant name Auburn National Bancorporation, Inc  
Trading Symbol AUBN  
entity small business true  
Entity Emerging Growth false  
Entity common stock shares outstanding   3,580,768
Amendment flag false  
Document Type 10-Q  
Document Year Focus 2019  
Document Period Focus Q1  
Document Period End Date Mar. 31, 2019