Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Rental revenue	$ 51,909	$ 46,231	$ 113,944
Property operating expenses	24,360	25,694	59,587
General and administrative	10,614	11,089	12,708
Advisory fee to related party	9,409	9,216	12,106
Interest Income	23,098	25,955	21,645
Interest expenses	35,004	39,860	66,063
Affiliate
Related Party Transaction [Line Items]
Rental revenue	1,083	841	144
Property operating expenses	990	991	254
General and administrative	3,869	4,429	1,267
Interest Income	19,515	23,670	5,406
Interest expenses	6,632	9,282	2,240
Affiliate \| Pillar and Regis
Related Party Transaction [Line Items]
Rental revenue	1,083	841	144
Affiliate \| Regis
Related Party Transaction [Line Items]
Property operating expenses	990	991	254
Affiliate \| Pillar
Related Party Transaction [Line Items]
General and administrative	3,869	4,429	1,267
Advisory fee to related party	9,409	9,216	12,106
Interest expenses	6,632	9,282	2,240
Affiliate \| UHF and Pillar
Related Party Transaction [Line Items]
Interest Income	$ 19,515	$ 23,670	$ 5,406
ARL \| MRHI \| Affiliate
Related Party Transaction [Line Items]
Ownership interest	91.00%

The amount of advisory fees to related parties, during the period.

No definition available.

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- Definition

Amount of expense incurred and directly related to generating revenue by lessor from operating lease of rented property and equipment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(2)(c))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

+ Details

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306

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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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