SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION - Footnotes (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Real Estate And Accumulated Depreciation
Unamortized discount (premium), net	$ 506
Aggregate cost for federal income tax purposes	9,030,197
Capital leases	$ 8,874
Buildings and Improvements \| Maximum
Real Estate And Accumulated Depreciation
Period over which real estate assets are depreciated, maximum	40 years
Equipment \| Maximum
Real Estate And Accumulated Depreciation
Period over which real estate assets are depreciated, maximum	12 years
Mortgages
Real Estate And Accumulated Depreciation
Mortgage debts	$ 689,361

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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))
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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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