Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Related Party Transaction [Line Items]
Rental revenues	$ 10,361	$ 11,442
Property operating expenses	5,832	6,309
General and administrative	3,235	4,292
Advisory fee to related party	2,436	2,373
Interest income	5,644	5,754
Interest expense	7,738	9,602
Affiliate
Related Party Transaction [Line Items]
Rental revenues	242	221
Property operating expenses	382	242
General and administrative	1,670	1,133
Interest income	4,769	5,073
Interest expense	1,395	1,915
Affiliate \| Pillar and Regis
Related Party Transaction [Line Items]
Rental revenues	242	221
Affiliate \| Regis
Related Party Transaction [Line Items]
Property operating expenses	382	242
Affiliate \| Pillar
Related Party Transaction [Line Items]
General and administrative	1,670	1,133
Advisory fee to related party	2,436	2,373
Interest expense	1,395	1,915
Affiliate \| UHF and Pillar
Related Party Transaction [Line Items]
Interest income	$ 4,769	$ 5,073
Affiliate \| ARL \| MRHI
Related Party Transaction [Line Items]
Ownership interest	90.80%

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

No definition available.

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Balance Type:	debit
Period Type:	duration

- 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

+ Details

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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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Balance Type:	debit
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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

+ Details

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Balance Type:	debit
Period Type:	duration

- 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121561866&loc=SL77919311-209978

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-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

+ Details

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Balance Type:	credit
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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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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