Auburn National Bancorporation - Parent Only, Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets:
Cash And Due From Banks	$ 14,868	$ 15,172
Premises and equipment, net	22,193	14,743
Other assets	7,920	6,872
Total assets	956,597	827,879
Liabilities:
Accrued expenses and other liabilities	6,723	4,330
Total liabilities	848,907	729,551
Stockholders' equity:
Total stockholders' equity	107,690	98,328	$ 89,055
Total liabilities and stockholders' equity	956,597	827,879
Parent Company [Member]
Assets:
Cash And Due From Banks	4,049	4,119
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	103,695	94,837
Other assets	631	625
Total assets	108,375	99,581
Liabilities:
Accrued expenses and other liabilities	685	1,253
Total liabilities	685	1,253
Stockholders' equity:
Total stockholders' equity	107,690	98,328
Total liabilities and stockholders' equity	$ 108,375	$ 99,581