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Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 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 | 152 | (343)
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, March 31 | 6,874 | 7,245
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 61 | (157)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 152 | (343)
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 | 2,405 | (6,529)
Purchases | 24,799 | 2,964
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (4,044) | (69)
Transfers into Level 3 | 361 | 17,055
Transfers out of Level 3 | 0 | (2,941)
Fair value, March 31 | 211,585 | 122,802
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 72 | (1,809)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 2,405 | (6,529)
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 | 696 | (4,335)
Purchases | 13,403 | 27,033
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (1,192) | (136)
Transfers into Level 3 | 14,148 | 0
Transfers out of Level 3 | (534) | (16,096)
Fair value, March 31 | 179,758 | 130,918
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | (73) | (472)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 696 | (4,335)
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, March 31 |  | 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 | 17 | (415)
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (3) | (11)
Transfers into Level 3 | 2,848 | 0
Transfers out of Level 3 | 0 | (3,431)
Fair value, March 31 | 3,236 | 439
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 | 17 | (415)
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 | 0 |
Transfers out of Level 3 | 0 |
Fair value, March 31 | 628 |
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | (269) |
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 | 3,270 | (11,639)
Purchases | 38,202 | 29,997
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (5,239) | (227)
Transfers into Level 3 | 17,357 | 17,055
Transfers out of Level 3 | (534) | (22,685)
Fair value, March 31 | 402,081 | 261,404
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | (209) | (2,445)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 3,270 | (11,639)
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) in the period included in net income | 61 | (157)
Gain (Loss) on Investments [Member] | Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) in the period included in net income | 72 | (1,809)
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) in the period included in net income | (73) | (472)
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) in 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) in 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) in the period included in net income | (269) |
Gain (Loss) on Investments [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) in the period included in net income | (209) | (2,445)
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) in 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) in the period included in net income | 12 | 4
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) in the period included in net income | (32) | 15
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) in 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) in the period included in net income | (1) | 47
Net Investment Income Earned [Member] | Common Stock [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net gains (losses) in 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) in the period included in net income | $ (21) | $ 66

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