Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Mar. 08, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	0-26486
Entity registrant name	Auburn National Bancorporation, Inc.
Entity incorporatoin state	DE
Entity tax identification number	63-0885779
Entity Address Line 1	132 N. Gay Street
Entity Address city	Auburn,
Entity Address State	AL
Entity Address Postal Zip Code	36830
City Area Code	334
Local Phone Number	821-9200
Entity current reporting status	Yes
Entity filer category	Non-accelerated Filer
Entity Interactive Data Status Current	Yes
entity small business	true
Entity Emerging Growth	false
ICFR Audit Attestation Flag	false
Entity Shell Company	false
Entity common stock shares outstanding		3,566,326
Entity public float			$ 132,361,395
Entity central index key	0000750574
Current fiscal year end date	--12-31
Document Year Focus	2020
Document Period Focus	FY
Amendment flag	false
Entity well known seasoned issuer	No
Entity voluntary filers	No
Security 12B Title	Common Stock
Trading Symbol	AUBN
Security Exchange	NASDAQ