ORGANIZATION AND BACKGROUND	12 Months Ended
Dec. 31, 2020
ORGANIZATION AND BACKGROUND
ORGANIZATION AND BACKGROUND	NOTE 1—ORGANIZATION AND BACKGROUND One Liberty Properties, Inc. (“OLP”) was incorporated in 1982 in Maryland. OLP is a self-administered and self-managed real estate investment trust (“REIT”). OLP acquires, owns and manages a geographically diversified portfolio consisting primarily of industrial, retail, restaurant, health and fitness, and theater properties, many of which are subject to long-term net leases. As of December 31, 2020, OLP owns 123 properties, including four properties owned by consolidated joint ventures and three properties owned by unconsolidated joint ventures. The 123 properties are located in 31 states.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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