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Summary of Significant Accounting Policies Significant Accounting Policies (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Accounting Policies [Abstract] |  |  |  |  |
Treasury money market funds, at fair value | $ 178.0 |  | $ 178.0 |  | $ 149.5
Deferred Costs | 17.7 |  | 17.7 |  | $ 16.1
Amortization of Deferred Charges | $ 1.1 | $ 1.1 | $ 3.3 | $ 3.6 |

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- Definition The amount of amortization of deferred charges applied against earnings during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(3)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
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