Short-term Borrowings (Details)	Sep. 30, 2019 USD ($) bank	Dec. 31, 2018 USD ($)	[1]
Line of Credit Facility [Line Items]
Customer repurchase agreements	$ 38,924,000	$ 35,243,000
First Two Correspondent Banks
Line of Credit Facility [Line Items]
Federal funds line of credit, number of banks | bank	1
Federal funds line of credit, amount per agreement	$ 15,000,000
Third Correspondent Bank
Line of Credit Facility [Line Items]
Federal funds line of credit, amount per agreement	$ 10,000,000

[1] Derived from audited consolidated financial statements.