Organization	12 Months Ended
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	OrganizationOffice Properties Income Trust, or OPI, we, us or our, is a real estate investment trust, or REIT, formed in 2009 under Maryland law.As of December 31, 2021, our wholly owned properties were comprised of 178 properties containing approximately 23,271,000 rentable square feet and we had noncontrolling ownership interests of 51% and 50% in two unconsolidated joint ventures that own three properties totaling approximately 444,000 rentable square feet.

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-URI http://asc.fasb.org/topic&trid=2122149

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-URI http://asc.fasb.org/topic&trid=2197479

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