Basis of Presentation (Policies)	9 Months Ended
Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation	The consolidated financial statements include: the accounts of OceanFirst Financial Corp. (the “Company”), its wholly-owned subsidiaries, OceanFirst Bank N.A. (the “Bank”) and OceanFirst Risk Management, Inc.; the Bank’s direct and indirect wholly-owned subsidiaries, OceanFirst REIT Holdings, Inc., OceanFirst Management Corp., OceanFirst Realty Corp., Casaba Real Estate Holdings Corporation, and Country Property Holdings, Inc; and a majority controlling interest in Trident Abstract Title Agency, LLC. Certain other subsidiaries were dissolved in 2022 and are included in the consolidated financial statements for previous periods. All significant intercompany accounts and transactions have been eliminated in consolidation.

Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126899994&loc=d3e18823-107790

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=109239629&loc=d3e5614-111684

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