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Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Summary Of Significant Accounting Policies [Line Items] |  |  |
Interest capitalized | $ 52,130,000 | $ 53,097,000 | $ 53,881,000
Salaries And Related Costs Capitalized | 16,100,000 | 13,700,000 | 12,900,000
Cash FDIC Insured Limit | 250,000 |  |
Separate Unrestricted Cash For Deferred Compensation Plan. | 32,300,000 | 43,600,000 |
Gains (losses) from investments in securities | $ (6,453,000) | 5,626,000 | 5,261,000
Accounts Receivable, Collection Period Expected | 1 |  |
Straight Line Rent Adjustments | $ 108,000,000 | 104,300,000 | 104,900,000
Above and below market rent adjustments, net | $ 9,100,000 | 4,200,000 | 6,500,000
REIT Distribution Requirement | 90.00% |  |
Company's Taxable Income Distribution | 100.00% |  |
Unrealized Gain (Loss) on Investments | $ (150,000) | $ 0 | $ 0
Environmental Focused Investment Fund |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Unrealized Gain (Loss) on Investments | $ (200,000) |  |

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