Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Estimated Fair Value	$ 408,037	$ 406,549
Mutual funds held in deferred compensation trust
Mutual Funds Held In Deferred Compensation Trust	1,410	1,510
Level 1 | Mutual funds held in deferred compensation trust
Mutual Funds Held In Deferred Compensation Trust	0	0
Level 1 | U.S. Treasuries
Estimated Fair Value	0	0
Level 2 | Mutual funds held in deferred compensation trust
Mutual Funds Held In Deferred Compensation Trust	1,410	1,510
Level 2 | U.S. Treasuries
Estimated Fair Value	10,369	7,889
Level 3 | U.S. Government Sponsored Enterprises
Estimated Fair Value	0	0
Level 3 | Mortgage-Backed Securities
Estimated Fair Value	0	0
Level 3 | Mutual funds held in deferred compensation trust
Mutual Funds Held In Deferred Compensation Trust	0	0
US Treasury Securities [Member]
Estimated Fair Value	10,369	7,889
U.S. Government Sponsored Enterprises [Member]
Estimated Fair Value	13,408	14,267
U.S. Government Sponsored Enterprises [Member] | Level 1
Estimated Fair Value	0	0
Mortgage-Backed Securities
Estimated Fair Value	224,655	217,152
Mortgage-Backed Securities | Level 1
Estimated Fair Value	0	0
State and Political Subdivisions
Estimated Fair Value	159,605	167,241
State and Political Subdivisions | Level 1
Estimated Fair Value	0	0
State and Political Subdivisions | Level 2
Estimated Fair Value	159,605	167,241
State and Political Subdivisions | Level 3
Estimated Fair Value	0	0
U.S. Government Sponsored Enterprises | Level 2
Estimated Fair Value	13,408	14,267
Mortgage-Backed Securities | Level 2
Estimated Fair Value	224,655	217,152
U.S. Treasuries | Level 3
Estimated Fair Value	$ 0	$ 0