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Summary of Significant Accounting Policies (Narrative) (Details) | 9 Months Ended |
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Sep. 30, 2025 USD ($) segment | Dec. 31, 2024 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |
Number of reportable segments | segment | 1 |
Monthly Fee to Participate in our Portfolio Program | $ 599 |
Cash and Cash Equivalents [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Uninsured cash and cash equivalents | 15,600,000 | $ 342,700,000
Restricted Cash and Cash Equivalents [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Uninsured cash and cash equivalents | $ 478,600,000 | $ 497,000,000.0

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