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Schedule III: Real Estate and Accumulated Depreciation (Rollforward of Real Estate and Accumulated Deprecation) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
REAL ESTATE: |  |  |
Balance at beginning of period | $ 1,069,426 | $ 1,071,043 | $ 1,041,342
Changes during the period | 1,084,621 | 1,075,054 | 1,071,919
Less: Fully depreciated assets | (23) | (5,628) | (876)
Balance at end of the period | 1,084,598 | 1,069,426 | 1,071,043
ACCUMULATED DEPRECIATION: |  |  |
Balance at beginning of period | 370,557 | 350,122 | 324,499
Additions charged to operating expenses | 25,734 | 26,063 | 26,499
Subtotal of accumulated depreciation | 396,291 | 376,185 | 350,998
Less: Fully depreciated assets | (23) | (5,628) | (876)
Balance at end of the period | 396,268 | 370,557 | 350,122
Land |  |  |
REAL ESTATE: |  |  |
Changes during the period | 0 | (11,921) | 0
Buildings and leasehold improvements |  |  |
REAL ESTATE: |  |  |
Changes during the period | 15,002 | 5,842 | 31,134
Development and construction in progress |  |  |
REAL ESTATE: |  |  |
Changes during the period | $ 193 | $ 10,090 | $ (557)

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- Definition The subtotal of real estate asset balance excluding assets sold and write-off of fully depreciated assets. + References No definition available. + Details
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- Definition SEC Schedule, 12-28, Real Estate Companies, Investment In Real Estate, Fully Depreciated Assets + References No definition available. + Details
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- Definition Amount of accumulated depreciation pertaining to real estate investments for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28(Column F)) -URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024 + Details
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- Definition Amount of other additions to accumulated depreciation other than depreciation expense for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28(Footnote 4)) -URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024 + Details
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- Definition Amount of increase (decrease) in accumulated depreciation on real estate investments for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28(Footnote 4)) -URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024 + Details
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- Definition Amount of decrease to accumulated depreciation for real estate investments sold for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28(Footnote 4)) -URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024 + Details
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- Definition Amount, before accumulated depreciation, of real estate investment by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. Excludes real estate not held as investment or interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28(Column E)) -URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024 + Details
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