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Summary Of Significant Accounting Policies of Tax Treatment of Common Dividends Per Share for Federal Tax Purposes (Details) - $ / shares |  |  |  |  |  |  |  |  |  |  |  |  | 3 Months Ended | 12 Months Ended |
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Oct. 31, 2025 | Jul. 31, 2025 | Apr. 30, 2025 | Jan. 30, 2025 | Oct. 31, 2024 | Jul. 31, 2024 | Apr. 30, 2024 | Jan. 30, 2024 | Oct. 31, 2023 | Jul. 31, 2023 | Apr. 28, 2023 | Jan. 30, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 18, 2025
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends treatment for federal tax purposes. |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3.64 | [1] | $ 3.65 | [2] | $ 4.16 | [3] |
Dividends Treatment For Federal Tax Purposes, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  | 100.00% |  | 100.00% |  |
Distributions Payable, Amount Per Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.70
Dividends, Per Unit, Cash Paid | $ 0.70 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 | $ 0.98 |  |  |  |  |  |  |
Tax Year 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends, Per Unit, Cash Paid |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.71 |  |  |  |  |  |  |
Tax Year 2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends, Per Unit, Cash Paid |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.27 |  |  |  |  |  |  |
Ordinary income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends treatment for federal tax purposes. |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2.35 |  | $ 3.22 |  | $ 3.04 |  |
Dividends Treatment For Federal Tax Purposes, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 64.52% |  | 88.29% |  | 72.98% |  |
Capital Gain Income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends treatment for federal tax purposes. |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.29 |  | $ 0.03 |  | $ 1.12 |  |
Dividends Treatment For Federal Tax Purposes, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.48% |  | 0.79% |  | 27.02% |  |
Return of Capital |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends treatment for federal tax purposes. |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  | $ 0.40 |  | $ 0 |  |
Dividends Treatment For Federal Tax Purposes, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  | 10.92% |  | 0.00% |  |
[1] | The fourth quarter 2025 regular quarterly dividend was $0.70 per common share, all of which was allocated to 2026.
[2] | The fourth quarter 2024 regular quarterly dividend was $0.98 per common share, all of which was allocated to 2025.
[3] | The fourth quarter 2023 regular quarterly dividend was $0.98 per common share, of which approximately $0.27 per common share was allocated to 2023 and approximately $0.71 per common share was allocated to 2024.

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