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Fair Value Measurements - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2023 USD ($) land_parcel property | Dec. 31, 2019
Assets and liabilities measured at fair value on a recurring and nonrecurring basis |  |
Number of impaired parcels of land | land_parcel | 1 |
Other segment |  |
Assets and liabilities measured at fair value on a recurring and nonrecurring basis |  |
Number of impaired operating real estate properties | property | 6 |
Impairment losses | $ 252,800 |
Real estate, fair value disclosure | 311,300 |
Fair value measurement on a recurring basis |  |
Assets and liabilities measured at fair value on a recurring and nonrecurring basis |  |
Marketable securities in deferred compensation plan | 1,748 |
Fair value measurement on a recurring basis | Deferred compensation plan | Trustees and Management |  |
Assets and liabilities measured at fair value on a recurring and nonrecurring basis |  |
Maximum percentage of participants' compensation which is deferrable |  | 100.00%
Marketable securities in deferred compensation plan | $ 1,700 |

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