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Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022
Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | $ 6,661 | $ 7,745
Total net gains (losses) for the period included in OCI | (80) | (879)
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Fair value, September 30 | 6,643 | 6,711
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 62 | (155)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | (80) | (879)
Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 187,980 | 114,127
Total net gains (losses) for the period included in OCI | (517) | (23,847)
Purchases | 77,567 | 74,327
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (7,437) | (8,663)
Transfers into Level 3 | 2,238 | 19,214
Transfers out of Level 3 | 0 | (7,038)
Fair value, September 30 | 260,479 | 165,824
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 289 | (2,330)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | (528) | (23,852)
Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 153,342 | 124,909
Total net gains (losses) for the period included in OCI | (2,433) | (11,436)
Purchases | 60,015 | 44,167
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (4,343) | (6,678)
Transfers into Level 3 | 14,148 | 0
Transfers out of Level 3 | (10,200) | (24,646)
Fair value, September 30 | 210,407 | 125,672
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | (110) | (771)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | (2,433) | (11,395)
Residential Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 |  | 245
Total net gains (losses) for the period included in OCI |  | (17)
Purchases |  | 0
Sales |  | 0
Issuances |  | 0
Settlements |  | (11)
Transfers into Level 3 |  | 0
Transfers out of Level 3 |  | (217)
Fair value, September 30 |  | 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 Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 375 | 4,256
Total net gains (losses) for the period included in OCI | 35 | (477)
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (24) | (15)
Transfers into Level 3 | 2,848 | 0
Transfers out of Level 3 | (2,626) | (3,430)
Fair value, September 30 | 344 | 373
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 0 | (7)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 35 | (477)
Common Stock [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 897 |
Total net gains (losses) for the period included in OCI | 0 |
Purchases | 0 |
Sales | 0 |
Issuances | 0 |
Settlements | 0 |
Transfers into Level 3 | 193 |
Transfers out of Level 3 | 0 |
Fair value, September 30 | 933 |
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | (157) |
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 0 |
Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 349,255 | 251,282
Total net gains (losses) for the period included in OCI | (2,995) | (36,656)
Purchases | 137,582 | 118,494
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (11,804) | (15,367)
Transfers into Level 3 | 19,427 | 19,214
Transfers out of Level 3 | (12,826) | (35,331)
Fair value, September 30 | 478,806 | 298,580
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 84 | (3,263)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | (3,006) | (36,620)
Gain (Loss) on Investments [Member] | Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | 62 | (155)
Gain (Loss) on Investments [Member] | Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | 289 | (2,345)
Gain (Loss) on Investments [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | (110) | (771)
Gain (Loss) on Investments [Member] | Residential Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [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 Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | 0 | (7)
Gain (Loss) on Investments [Member] | Common Stock [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | (157) |
Gain (Loss) on Investments [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | 84 | (3,278)
Net Investment Income Earned [Member] | Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [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 Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | 359 | 49
Net Investment Income Earned [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | (12) | 127
Net Investment Income Earned [Member] | Residential Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [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 Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | (264) | 46
Net Investment Income Earned [Member] | Common Stock [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | 0 |
Net Investment Income Earned [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) for the period included in net income | $ 83 | $ 222

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