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Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	$ 349,255	$ 251,282
Purchases	201,681	200,274
Sales	0	0
Issuances	0	0
Settlements	(27,016)	(22,535)
Transfers into Level 3	38,485	20,613
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(26,062)	(60,938)
Fair Value, End of Year	551,689	349,255
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	241	(3,374)
Change in unrealized (gains) losses for the period included in OCI for assets held at period end	14,652	36,359
Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	6,661	7,745
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0
Fair Value, End of Year	7,834	6,661
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	62	(99)
Change in unrealized (gains) losses for the period included in OCI for assets held at period end	1,111	(985)
Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	187,980	114,127
Purchases	97,547	99,868
Sales	0	0
Issuances	0	0
Settlements	(10,254)	(10,148)
Transfers into Level 3	21,297	19,214
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(10,923)	(9,111)
Fair Value, End of Year	297,332	187,980
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	419	(2,399)
Change in unrealized (gains) losses for the period included in OCI for assets held at period end	10,634	23,630
Collateralized Loan Obligations and Other Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	153,342	124,909
Purchases	104,134	100,406
Sales	0	0
Issuances	0	0
Settlements	(16,737)	(12,361)
Transfers into Level 3	14,148	502
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(12,513)	(48,180)
Fair Value, End of Year	245,313	153,342
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	(5)	(876)
Change in unrealized (gains) losses for the period included in OCI for assets held at period end	2,858	(11,246)
Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	0	245
Purchases		0
Sales		0
Issuances		0
Settlements		(11)
Transfers into Level 3		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		(217)
Fair Value, End of Year		0
Change in unrealized gains (losses) for the period included in earnings for assets held at period end		0
Change in unrealized (gains) losses for the period included in OCI for assets held at period end		(17)
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	375	4,256
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	(25)	(15)
Transfers into Level 3	2,848	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(2,626)	(3,430)
Fair Value, End of Year	356	375
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	0	0
Change in unrealized (gains) losses for the period included in OCI for assets held at period end	49	(481)
Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Beginning of Year	897	0
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	192	897
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0
Fair Value, End of Year	854	897
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	235	0
Change in unrealized (gains) losses for the period included in OCI for assets held at period end	0	0
Gain (Loss) on Investments [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	241	(3,389)
Gain (Loss) on Investments [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	62	(99)
Gain (Loss) on Investments [Member] | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	419	(2,414)
Gain (Loss) on Investments [Member] | Collateralized Loan Obligations and Other Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	(5)	(876)
Gain (Loss) on Investments [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income		0
Gain (Loss) on Investments [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	0	0
Gain (Loss) on Investments [Member] | Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	(235)	0
Net Investment Income Earned [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	326	342
Net Investment Income Earned [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	0	0
Net Investment Income Earned [Member] | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	621	68
Net Investment Income Earned [Member] | Collateralized Loan Obligations and Other Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	(30)	229
Net Investment Income Earned [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income		0
Net Investment Income Earned [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	(265)	45
Net Investment Income Earned [Member] | Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in net income	0	0
Other Comprehensive Income (Loss) | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI	14,779	(36,394)
Other Comprehensive Income (Loss) | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI	1,111	(985)
Other Comprehensive Income (Loss) | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI	10,645	(23,624)
Other Comprehensive Income (Loss) | Collateralized Loan Obligations and Other Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI	2,974	(11,287)
Other Comprehensive Income (Loss) | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI		(17)
Other Comprehensive Income (Loss) | Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI	49	(481)
Other Comprehensive Income (Loss) | Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net gains (losses) for the period included in OCI	$ 0	$ 0

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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