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Summary Of Significant Accounting Policies (Narrative) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($) | Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Separate Unrestricted Cash For Deferred Compensation Plan. | $ 40,900 |  | $ 40,900 |  | $ 39,400
Gains from investments in securities | 2,600 | $ 315 | 2,235 | $ 2,587 |
Prepaid Expense and Other Assets | 89,624 |  | 89,624 |  | 70,839
Unsecured commercial paper | $ 750,000 |  | $ 750,000 |  | 500,000
Number of VIEs | 12 |  | 12 |  |
Commercial Paper |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Unsecured commercial paper | $ 750,000 |  | $ 750,000 |  |
Unconsolidated Joint Ventures [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of VIEs | 3 |  | 3 |  |
Deferred Compensation, Excluding Share-Based Payments and Retirement Benefits |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Gains from investments in securities | $ 2,600 | $ 300 | $ 2,200 | $ 2,600 |
Environmental Focused Investment Fund |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Prepaid Expense and Other Assets | 8,600 |  | 8,600 |  | 7,100
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Prepaid Expense and Other Assets | $ 18,569 |  | $ 18,569 |  | $ 15,036
Number of VIEs | 9 |  | 9 |  |
Commercial Real Estate Properties [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of VIEs | 6 |  | 6 |  |

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