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Schedule III - Real Estate and Accumulated Depreciation (Activity in Real Estate and Accumulated Depreciation) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Changes in real estate |  |  |
Balance at beginning of year | $ 8,513,935 | $ 10,206,122 | $ 12,743,332
Property acquisitions | 0 | 52,939 | 13,323
Improvements | 251,674 | 267,726 | 342,014
Retirements/disposals/deconsolidation | 18,958 | (2,012,852) | (2,892,547)
Balance at end of year | 8,784,567 | 8,513,935 | 10,206,122
Aggregate cost of land, buildings and improvements before depreciation | 10,300,000 |  |
Changes in accumulated depreciation |  |  |
Balance at beginning of year | 2,099,137 | 2,300,116 | 2,264,694
Depreciation for year | 222,867 | 245,033 | 347,015
Retirements/disposals/deconsolidation | (261,444) | (446,012) | (311,593)
Balance at end of year | $ 2,060,560 | $ 2,099,137 | $ 2,300,116

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- Definition The amount that was removed from accumulated depreciation pertaining to real estate that was sold, retired or deconsolidated in the period. + References No definition available. + Details
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- Definition The carrying amount of real estate sold, retired or deconsolidated during the period. + References No definition available. + Details
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- Definition Cost basis of real estate investments for federal income tax purposes 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 SEC -Name Regulation S-X (SX) -Number 210 -Section 12 -Footnote 6 -Subsection 28 Reference 2: 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 6)) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + 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 http://asc.fasb.org/extlink&oid=6590653&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 http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + Details
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- Definition Amount of increase in real estate investments related to improvements 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 http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + Details
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- Definition Amount of increase in real estate investments from acquisitions other than through foreclosure 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 http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + Details
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- Definition Amount of depreciation expense of 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(Footnote 4)) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + Details
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