Note 18 - Merger (Details Textual) $ / shares in Units, $ in Billions	Aug. 24, 2023 USD ($) $ / shares	Mar. 31, 2024 $ / shares	Dec. 31, 2023 $ / shares	[1]
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 2.5	$ 2.5
Burke & Herbert [Member]
Net Assets | $	$ 3.6
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.5
Burke & Herbert [Member] | Agreement and Plan of Reorganization, Merger [Member]
Business Acquisition, Effective Date of Acquisition	May 03, 2024
Burke & Herbert [Member] | Agreement and Plan of Reorganization, Merger [Member]
Business Combination, Conversion of Stock, Ratio	0.5043
Summit [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 2.5

[1] Derived from audited consolidated financial statements.