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Properties, Net (Operating properties, net) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | --- | ---
Operating properties, net |  |  |  |
Gross | $ 4,686,802 | $ 4,348,006 | $ 4,148,529 | $ 3,980,813
Operating properties, net | 3,115,280 | 2,772,647 |  |
Operating properties, net |  |  |  |
Operating properties, net |  |  |  |
Less: accumulated depreciation | (1,124,253) | (1,007,120) |  |
Operating properties, net | 3,115,280 | 2,772,647 |  |
Operating properties, net | Land |  |  |  |
Operating properties, net |  |  |  |
Gross | 528,269 | 472,976 |  |
Operating properties, net | Buildings and improvements |  |  |  |
Operating properties, net |  |  |  |
Gross | $ 3,711,264 | $ 3,306,791 |  |

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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 http://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024 + Details
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- Definition The cumulative amount of depreciation for real estate property held for investment purposes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(3)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Carrying amount of income producing properties held for rental. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(d)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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- Details
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- Details
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