Lessor, Operating Lease, Lease Not yet Commenced, Annual Base Rent

No definition available.

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Namespace Prefix:	opi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessor, Operating Lease, Lease Not yet Commenced, Annual Base Rent Increase Period

+ References

No definition available.

+ Details

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- Definition

Lessor, Operating Lease, Lease Not yet Commenced, Annual Percentage Increase

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Lessor, Operating Lease, Lease Not yet Commenced, Number Of Renewal Options

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the number of agreements with RMR LLC to provide management services to the company.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Joint Ventures

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Term of lessor's operating lease renewal for lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-3

+ Details

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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 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 2: 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)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 3: 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//1943274/2147483575/946-220-S99-1

+ Details

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- Details

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- Details

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- Details

Name:	srt_CounterpartyNameAxis=opi_SonestaInternationalHotelsCorporationMember
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Related Person Transactions (Details) $ in Thousands		1 Months Ended	3 Months Ended
Related Person Transactions (Details) $ in Thousands	Mar. 31, 2024 joint_venture	Jun. 30, 2021 USD ($) ft² renewal_option	Mar. 31, 2024 USD ($) joint_venture agreement	Mar. 31, 2023 USD ($)
Related Party Transaction [Line Items]
Number of joint ventures \| joint_venture	2		2
Rental income			$ 139,435	$ 132,422
Related Party \| RMR LLC
Related Party Transaction [Line Items]
Number of agreements \| agreement			2
Rental income			$ 194	$ 223
Related Party \| Sonesta
Related Party Transaction [Line Items]
Rental income			$ 2,775
Rentable square feet (in square feet) \| ft²		230,000
Number of renewal options \| renewal_option		2
Renewal term		10 years
Annual base rent		$ 6,436
Annual percentage increase		10.00%
Annual base rent increase period		5 years