Overall summary of real estate and accumulated depreciation.

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- Definition

Total number of properties which the company directly or indirectly through investments in title holding entities owns all or a portion of.

+ References

No definition available.

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- Definition

Total number of units associated with rental properties which the company directly or indirectly through investments in title holding entities owns all or a portion of.

+ References

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- Definition

Amount of lien or mortgage outstanding on real estate investment properties 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
-Paragraph Column B
-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(Column B))
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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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

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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

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- Definition

Amount after accumulated depreciation of real estate held for investment 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)
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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Schedule III - Real Estate and Accumulated Depreciation-Overall Summary (Details)	Dec. 31, 2018 USD ($) Property ApartmentUnit	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Overall summary of real estate and accumulated depreciation
Investment in Real Estate, Gross	$ 26,511,022,000	$ 26,026,896,000	$ 25,386,425,000	$ 28,542,697,000
Accumulated Depreciation	$ (6,696,281,000)	$ (6,040,378,000)	$ (5,360,389,000)	$ (6,084,616,000)
Investment in Real Estate - Wholly Owned Unencumbered [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	240
Units \| ApartmentUnit	62,862
Investment in Real Estate, Gross	$ 21,609,130,732
Accumulated Depreciation	(5,400,484,879)
Investment in Real Estate, Net	16,208,645,853
Encumbrances	$ 0
Investment in Real Estate - Wholly Owned Encumbered [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	48
Units \| ApartmentUnit	12,140
Investment in Real Estate, Gross	$ 4,023,117,169
Accumulated Depreciation	(1,039,436,780)
Investment in Real Estate, Net	2,983,680,389
Encumbrances	$ 2,081,887,149
Wholly Owned Properties
Overall summary of real estate and accumulated depreciation
Properties \| Property	288
Units \| ApartmentUnit	75,002
Investment in Real Estate, Gross	$ 25,632,247,901
Accumulated Depreciation	(6,439,921,659)
Investment in Real Estate, Net	19,192,326,242
Encumbrances	$ 2,081,887,149
Investment in Real Estate - Partially Owned Unencumbered [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	9
Units \| ApartmentUnit	1,847
Investment in Real Estate, Gross	$ 516,719,235
Accumulated Depreciation	(116,736,579)
Investment in Real Estate, Net	399,982,656
Encumbrances	$ 0
Investment in Real Estate - Partially Owned Encumbered [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	8
Units \| ApartmentUnit	1,688
Investment in Real Estate, Gross	$ 362,054,538
Accumulated Depreciation	(139,622,501)
Investment in Real Estate, Net	222,432,037
Encumbrances	$ 303,583,335
NONCONTROLLING INTERESTS - PARTIALLY OWNED PROPERTIES
Overall summary of real estate and accumulated depreciation
Properties \| Property	17
Units \| ApartmentUnit	3,535
Investment in Real Estate, Gross	$ 878,773,773
Accumulated Depreciation	(256,359,080)
Investment in Real Estate, Net	622,414,693
Encumbrances	$ 303,583,335
Unencumbered Properties [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	249
Units \| ApartmentUnit	64,709
Investment in Real Estate, Gross	$ 22,125,849,967
Accumulated Depreciation	(5,517,221,458)
Investment in Real Estate, Net	16,608,628,509
Encumbrances	$ 0
Encumbered Properties [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	56
Units \| ApartmentUnit	13,828
Investment in Real Estate, Gross	$ 4,385,171,707
Accumulated Depreciation	(1,179,059,281)
Investment in Real Estate, Net	3,206,112,426
Encumbrances	$ 2,385,470,484
Total Consolidated Investment in Real Estate [Member]
Overall summary of real estate and accumulated depreciation
Properties \| Property	305
Units \| ApartmentUnit	78,537
Investment in Real Estate, Gross	$ 26,511,021,674
Accumulated Depreciation	(6,696,280,739)
Investment in Real Estate, Net	19,814,740,935
Encumbrances	$ 2,385,470,484