Parent-Only Financial Information - Schedule of Condensed Statement of Financial Condition (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assets
Cash and due from banks	$ 153,718	$ 167,946	$ 204,949	$ 1,272,134
Goodwill	506,146	506,146
Other assets	179,661	221,067
Total assets	13,538,253	13,103,896
Liabilities and Stockholders’ Equity
Borrowings	1,118,240	1,475,666
Other liabilities	300,712	346,155
OceanFirst Financial Corp. stockholders’ equity	1,661,163	1,584,662
Non-controlling interest	782	802
Total stockholders’ equity	1,661,945	1,585,464	1,516,553	1,484,130
Total liabilities and stockholders’ equity	13,538,253	13,103,896
OceanFirst Financial Corp.
Assets
Cash and due from banks	12,083	10,623	$ 8,803	$ 7,187
Advances to Bank	67,289	32,840
Equity securities	93,387	95,261
ESOP loan receivable	4,241	6,751
Investment in subsidiaries	1,672,406	1,630,199
Goodwill	5,827	5,827
Other assets	6,059	1,760
Total assets	1,861,292	1,783,261
Liabilities and Stockholders’ Equity
Borrowings	194,771	193,469
Other liabilities	4,576	4,328
OceanFirst Financial Corp. stockholders’ equity	1,661,163	1,584,662
Non-controlling interest	782	802
Total stockholders’ equity	1,661,945	1,585,464
Total liabilities and stockholders’ equity	$ 1,861,292	$ 1,783,261