Condensed Financial Statements of Parent Company (Additional Information) (Details) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Preferred stock, shares authorized	250,000	250,000
Preferred stock, par value	$ 1.00	$ 1.00
Common stock, par value	$ 2.50	$ 2.50
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	12,985,708	12,474,641
Common stock, shares outstanding	12,942,004	12,408,542
Employee Stock Ownership Plan (ESOP), Number of Suspense Shares	43,704	66,099