Schedule III - Real Estate and Accumulated Depreciation - Real Estate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Balance at January 1	$ 2,710,512	$ 2,577,195	$ 2,997,351
Improvements and additions	134,035	203,124	167,676
Acquisitions through foreclosure	0	4,600	0
Other acquisitions	231,436	762,207	5,164
Dispositions	(464,648)	(656,900)	(561,431)
Other	(236,545)	0	0
Impairments	(10,377)	(179,714)	(31,565)
Balance at December 31	$ 2,364,413	$ 2,710,512	$ 2,577,195

Amount of improvements and additions made to real estate investments during the period.

No definition available.

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- Definition

Amount of real estate investments acquired 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

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- Definition

Amount of real estate investments sold for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

+ 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

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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

+ Details

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- Definition

Amount of other additions excluding acquisition or improvement to real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of write-down or reserve recognized in the income statement 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Footnote 5))
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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