Investments, Gross Unrealized Losses and Fair Value and Net Unrealized Gains (Losses) (Details) $ in Thousands	Jun. 30, 2023 USD ($) Security	Dec. 31, 2022 USD ($)
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Number of securities owned with fair value less than cost \| Security	348
Less than twelve months, Fair value	$ 30,572	$ 181,562
Less than twelve months, Gross unrealized losses	(805)	(11,648)
Twelve months or greater, Fair value	393,166	246,164
Twelve months or greater, Gross unrealized losses	(43,926)	(35,889)
Total, Fair value	423,738	427,726
Total, Gross Unrealized Losses	(44,731)	(47,537)
U.S. Agency Securities [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	4,631	39,729
Less than twelve months, Gross unrealized losses	(120)	(1,892)
Twelve months or greater, Fair value	62,236	30,948
Twelve months or greater, Gross unrealized losses	(7,077)	(5,987)
Total, Fair value	66,867	70,677
Total, Gross Unrealized Losses	(7,197)	(7,879)
U.S. Treasury Securities [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	0	32,673
Less than twelve months, Gross unrealized losses	0	(1,337)
Twelve months or greater, Fair value	149,791	115,897
Twelve months or greater, Gross unrealized losses	(12,574)	(12,329)
Total, Fair value	149,791	148,570
Total, Gross Unrealized Losses	(12,574)	(13,666)
Obligations of State and Political Subdivisions [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	6,423	66,725
Less than twelve months, Gross unrealized losses	(108)	(4,887)
Twelve months or greater, Fair value	89,377	35,782
Twelve months or greater, Gross unrealized losses	(8,821)	(5,410)
Total, Fair value	95,800	102,507
Total, Gross Unrealized Losses	(8,929)	(10,297)
Corporate Obligations [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	800	2,165
Less than twelve months, Gross unrealized losses	(200)	(165)
Twelve months or greater, Fair value	8,097	6,218
Twelve months or greater, Gross unrealized losses	(1,216)	(787)
Total, Fair value	8,897	8,383
Total, Gross Unrealized Losses	(1,416)	(952)
Mortgage-backed Securities in Government Sponsored Entities [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	18,718	40,270
Less than twelve months, Gross unrealized losses	(377)	(3,367)
Twelve months or greater, Fair value	83,665	57,319
Twelve months or greater, Gross unrealized losses	(14,238)	(11,376)
Total, Fair value	102,383	97,589
Total, Gross Unrealized Losses	$ (14,615)	$ (14,743)

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