Auburn National Bancorporation - Parent Only, Statement of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net earnings	$ 9,741	$ 8,834
Adjustments to reconcile net earnings to net cash provided by operating activties:
Depreciation and amortization	1,157	938
Net increase in other assets	(872)	(221)
Net increase in accrued expenses and other liabilities	1,807	(402)
Net cash provided by operating activities	10,850	12,141
Cash flows from investing activities:
Net cash used in investing activities	24,085	(12,054)
Cash flows from financing activities:
Stock repurchases	(2,721)	0
Repayments or retirement of long-term debt	0	(3,217)
Dividends paid	(3,575)	(3,498)
Net cash provided by (used in) financing activities	(7,568)	(40,539)
Net change in cash and cash equivalents	27,367	(40,452)
Cash and cash equivalents at beginning of period	65,076	105,528
Cash and cash equivalents at end of period	92,443	65,076
Parent Company [Member]
Cash flows from operating activities:
Net earnings	9,741	8,834
Adjustments to reconcile net earnings to net cash provided by operating activties:
Net increase in other assets	7	1,134
Net increase in accrued expenses and other liabilities	(215)	(70)
Equity In Distributed (Undistributed) Earnings Of Bank Subsidary	1,059	2,412
Net cash provided by operating activities	8,474	7,486
Cash flows from financing activities:
Stock repurchases	(2,721)	0
Repayments or retirement of long-term debt	0	(3,217)
Dividends paid	(3,575)	(3,498)
Net cash provided by (used in) financing activities	(6,296)	(6,715)
Net change in cash and cash equivalents	2,178	771
Cash and cash equivalents at beginning of period	1,941	1,170
Cash and cash equivalents at end of period	$ 4,119	$ 1,941