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Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2024 USD ($) segment | Dec. 31, 2023 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |
Number of reportable segments | segment | 1 |
Cash and Cash Equivalents [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Uninsured cash and cash equivalents | $ 158.6 | $ 12.8
Restricted Cash and Cash Equivalents [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Uninsured cash and cash equivalents | $ 551.8 | $ 453.7

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