Fair Value (Available-For-Sale Securities) (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Fair Value Disclosure [Line Items] | ||
| Amortized Cost | $ 145.8 | $ 91.9 |
| Gross Unrealized Gains | 2.4 | 0.5 |
| Gross Unrealized Losses | 2.1 | 5.6 |
| Allowance for Credit Loss | (0.0) | (0.1) |
| Fair Value | 146.1 | 86.7 |
| Debt and Equity Securities, Unrealized Gain (Loss) | 0.7 | |
| U.S. Treasury debt securities | ||
| Fair Value Disclosure [Line Items] | ||
| Amortized Cost | 9.5 | |
| Gross Unrealized Gains | 0.0 | |
| Gross Unrealized Losses | 0.0 | |
| Allowance for Credit Loss | 0.0 | |
| Fair Value | 9.5 | |
| Corporate/Other debt securities | ||
| Fair Value Disclosure [Line Items] | ||
| Amortized Cost | 136.3 | 91.9 |
| Gross Unrealized Gains | 2.4 | 0.5 |
| Gross Unrealized Losses | 2.1 | 5.6 |
| Allowance for Credit Loss | 0.0 | (0.1) |
| Fair Value | 136.6 | 86.7 |
| Debt Securities, Available-for-sale, Unrealized Loss Position | $ 40.2 | $ 70.1 |
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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of unrealized gain (loss) on investment in debt and equity securities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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