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Fair Value (Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3)) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning Balance | $ 38,200,000 | $ 27,100,000
Included in net realized and unrealized investment gains (losses) | $ 500,000 | $ 600,000
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Gain Loss On Investments From Continuing Operations | Gain Loss On Investments From Continuing Operations
Included in other comprehensive income (loss) - changes in net unrealized gains (losses) on investment securities | $ (600,000) | $ (500,000)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] | OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax | OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax
Settlements | $ (3,100,000) | $ (3,100,000)
Ending Balance | 36,200,000 | 38,200,000
Changes in net unrealized gains (losses) for the period included in other comprehensive income (loss) for assets held at the end of the year | $ (600,000) | $ (500,000)
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Gain Loss On Investments From Continuing Operations | Gain Loss On Investments From Continuing Operations
Municipals [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning Balance | $ 7,600,000 | $ 8,600,000
Included in other comprehensive income (loss) - changes in net unrealized gains (losses) on investment securities | 300,000 |
Settlements | (500,000) | (1,000,000)
Ending Balance | 7,400,000 | 7,600,000
Changes in net unrealized gains (losses) for the period included in other comprehensive income (loss) for assets held at the end of the year | 300,000 | 0
Corporates [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning Balance |  | 100,000
Transfers out of Level 3 |  | (100,000)
Commercial Mortgage-Backed [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning Balance | 5,900,000 | 7,000,000.0
Included in other comprehensive income (loss) - changes in net unrealized gains (losses) on investment securities | 300,000 | (500,000)
Settlements | (1,300,000) | (600,000)
Ending Balance | 4,900,000 | 5,900,000
Changes in net unrealized gains (losses) for the period included in other comprehensive income (loss) for assets held at the end of the year | 300,000 | (500,000)
Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning Balance | 13,500,000 | 15,700,000
Transfers out of Level 3 |  | (100,000)
Included in other comprehensive income (loss) - changes in net unrealized gains (losses) on investment securities | 600,000 | (500,000)
Settlements | (1,800,000) | (1,600,000)
Ending Balance | 12,300,000 | 13,500,000
Changes in net unrealized gains (losses) for the period included in other comprehensive income (loss) for assets held at the end of the year | 600,000 | (500,000)
Equities and Other [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning Balance | 24,700,000 | 11,400,000
Included in net realized and unrealized investment gains (losses) | 500,000 | 600,000
Addition |  | 14,200,000
Settlements | (1,300,000) | (1,500,000)
Ending Balance | $ 23,900,000 | $ 24,700,000

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- Definition Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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