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- Definition

Real Estate Owned, Property Management And Construction Supervision Fees

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- Definition

Related Party Transaction, Common Shares Ownership Percentage

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- Definition

Related Party Transaction, Shares Owned By Related Party

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- Definition

Shares To Purchase Through Rights Offering Percentage

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- Definition

Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column A
-Footnote 3
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478322/948-310-S50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column A)(Footnote 3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

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- Definition

Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G)(Footnote 3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478322/948-310-S50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

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- Definition

The percentage charged for managing real estate properties.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
-Publisher FASB
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

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- Definition

Cash received on stock transaction after deduction of issuance costs.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

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Related Person Transactions (Details) $ in Thousands					1 Months Ended	3 Months Ended		12 Months Ended
Related Person Transactions (Details) $ in Thousands	Dec. 11, 2025 shares	Dec. 04, 2025 shares	Nov. 10, 2025 USD ($) loan	Oct. 30, 2025 USD ($) shares	Jul. 31, 2023	Mar. 31, 2026 USD ($) loan shares	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($) loan	Dec. 31, 2024 USD ($)
Related Party Transaction [Line Items]
Number of loans \| loan						26		24
Amortized Cost \| $						$ 730,096	$ 660,237	$ 685,707	$ 609,916
Tremont Realty Advisors LLC \| Transferrable Rights Offering
Related Party Transaction [Line Items]
Sale of stock, percentage of ownership after transaction (as a percent)						20.30%
Shares issued (in shares)	2,015,748	854,029
The RMR Group Inc
Related Party Transaction [Line Items]
Property management agreement, termination notice period (in days)					30 days
Real estate owned, property management and construction supervision fees \| $						$ 20	$ 21
The RMR Group Inc \| Transferrable Rights Offering
Related Party Transaction [Line Items]
Shares owned (in shares)				5,517,113
Sale of stock, percentage of ownership after transaction (as a percent)				73.20%
Shares issued (in shares)				7,532,861
Net proceeds \| $				$ 65,200
Shares To Purchase Through Rights Offering Percentage (as a percent)				100.00%
Adam Portnoy \| Transferrable Rights Offering
Related Party Transaction [Line Items]
Shares owned (in shares)						5,085,332
Shares issued (in shares)		109,669
ABP Trust \| Transferrable Rights Offering
Related Party Transaction [Line Items]
Shares issued (in shares)		58,266
Management Services \| Tremont Realty Advisors LLC
Related Party Transaction [Line Items]
Shares owned (in shares)						4,577,835
Outstanding common shares (as a percent)						22.50%
Property Management Services \| The RMR Group Inc
Related Party Transaction [Line Items]
Property management fee (as a percent)					3.00%
Construction Supervision Services \| The RMR Group Inc
Related Party Transaction [Line Items]
Property management fee (as a percent)					5.00%
Purchase of Mortgage Loans
Related Party Transaction [Line Items]
Number of loans \| loan			2
Purchase of Mortgage Loans \| The RMR Group Inc
Related Party Transaction [Line Items]
Amortized Cost \| $			$ 61,733