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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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