Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2021
Summary of Signficant Accounting Policies
Nature of Business Policy	General Auburn National Bancorporation, Inc. (the “Company”) provides a full range of banking services to individual and corporate customers in Lee County, Alabama and surrounding counties through its wholly owned subsidiary, AuburnBank (the “Bank”). The Company does not have any segments other than banking that are considered material.
Basis of Presentation Policy	Basis of Presentation and Use of Estimates The unaudited consolidated financial statements in this report have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information. Accordingly, these financial statements do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. The unaudited consolidated financial statements include, in the opinion of management, all adjustments necessary to present a fair statement of the financial position and the results of operations for all periods presented. All such adjustments are of a normal recurring nature. The results of operations in the interim statements are not necessarily indicative of the results of operations that the Company and its subsidiaries may achieve for future interim periods or the entire year. For further information, refer to the consolidated financial statements and footnotes included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.
Consolidation Policy	The unaudited consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. Significant intercompany transactions and accounts are eliminated in consolidation.
Use of Estimates Policy	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the balance sheet date and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term include other-than-temporary impairment on investment securities, the determination of the allowance for loan losses, fair value of financial instruments, and the valuation of deferred tax assets and other real estate owned (“OREO”).
Revenue Recognition Policy	Revenue Recognition On January 1, 2018, the Company implemented Accounting Standards Update (“ASU” or “updates”) 2014-09, Revenue from Contracts with Customers , codified at Accounting Standards Codification (“ASC”) 606. The Company adopted ASC 606 using the modified retrospective transition method. The majority of the Company’s revenue stream is generated from interest income on loans and securities which are outside the scope of ASC 606. The Company’s sources of income that fall within the scope of ASC 606 include service charges on deposits, investment services, interchange fees and gains and losses on sales of other real estate, all of which are presented as components of noninterest income. The following is a summary of the revenue streams that fall within the scope of ASC 606: ● Service charges on deposits, investment services, ATM and interchange fees – Fees from these services are either transaction-based, for which the performance obligations are satisfied when the individual transaction is processed, or set periodic service charges, for which the performance obligations are satisfied over the period the service is provided. Transaction-based fees are recognized at the time the transaction is processed, and periodic service charges are recognized over the service period. ● Gains on sales of OREO – A gain on sale should be recognized when a contract for sale exists and control of the asset has been transferred to the buyer. ASC 606 lists several criteria required to conclude that a contract for sale exists, including a determination that the institution will collect substantially all of the consideration to which it is entitled. In addition to the loan-to-value, the analysis is based on various other factors, including the credit quality of the borrower, the structure of the loan, and any other factors that may affect collectability.
Subsequent Events Policy	Subsequent Events The Company has evaluated the effects of events and transactions through the date of this filing that have occurred subsequent to September 30, 2021. The Company does not believe there were any material subsequent events during this period that would have required further recognition or disclosure in the unaudited consolidated financial statements included in this report.
Accounting Developments	Accounting Developments In the first nine months of 2021, the Company did not adopt any new accounting guidance.