PARENT COMPANY ONLY - Condensed Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Other assets	$ 39,819	$ 32,730
TOTAL ASSETS	2,454,307	2,327,648
LIABILITIES AND STOCKHOLDERS' EQUITY
Senior notes, net	14,765	14,701
Subordinated debt, net	24,607	33,009
Accrued interest and other liabilities	25,608	23,628
Stockholders' equity	249,325	301,405	$ 299,756	$ 244,452
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	2,454,307	2,327,648
Parent Company
ASSETS
Cash	17,867	33,518
Other assets	33	33
TOTAL ASSETS	288,799	349,258
LIABILITIES AND STOCKHOLDERS' EQUITY
Senior notes, net	14,765	14,701
Subordinated debt, net	24,607	33,009
Accrued interest and other liabilities	102	143
Stockholders' equity	249,325	301,405
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	288,799	349,258
Subsidiaries | Citizens & Northern Bank
ASSETS
Investment in subsidiaries	254,809	298,797
Subsidiaries | Citizens & Northern Investment Corporation
ASSETS
Investment in subsidiaries	12,453	13,085
Subsidiaries | Bucktail Life Insurance Company
ASSETS
Investment in subsidiaries	$ 3,637	$ 3,825