v3.25.2
Cover - shares
 6 Months Ended
Jun. 30, 2025
Jul. 30, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-11713  
Entity Registrant Name OceanFirst Financial Corp  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 22-3412577  
Entity Address, Address Line One 110 West Front Street,  
Entity Address, City or Town Red Bank,  
Entity Address, State or Province NJ  
Entity Address, Postal Zip Code 07701  
City Area Code 732  
Local Phone Number 240-4500  
Title of 12(b) Security Common stock, $0.01 par value per share  
Trading Symbol OCFC  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   57,385,351
Amendment Flag false  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Entity Central Index Key 0001004702  
Current Fiscal Year End Date --12-31