Investments - Amortized Cost and Estimated Fair Value (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	$ 1,050,172,000	$ 957,459,000
Gross Unrealized Gains	2,751,000	18,769,000
Gross Unrealized Losses	(27,891,000)	(2,914,000)
Allowance for Credit Losses - AFS Securities	0	0
Estimated Fair Value	1,025,032,000	973,314,000
U.S. Government Agencies [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	9,695,000	1,546,000
Gross Unrealized Gains		28,000
Gross Unrealized Losses	(258,000)
Estimated Fair Value	9,437,000	1,574,000
Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	304,904,000	303,912,000
Gross Unrealized Gains	395,000	4,772,000
Gross Unrealized Losses	(11,881,000)	(1,957,000)
Estimated Fair Value	293,418,000	306,727,000
States and Political Subdivisions [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	294,077,000	290,729,000
Gross Unrealized Gains	2,356,000	13,807,000
Gross Unrealized Losses	(10,053,000)	(268,000)
Estimated Fair Value	286,380,000	304,268,000
Corporate Bond [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	44,755,000	28,436,000
Gross Unrealized Gains		94,000
Gross Unrealized Losses	(1,396,000)	(1,000)
Estimated Fair Value	43,359,000	28,529,000
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	396,741,000	332,836,000
Gross Unrealized Gains		68,000
Gross Unrealized Losses	(4,303,000)	(688,000)
Estimated Fair Value	$ 392,438,000	$ 332,216,000