Parent-Only Financial Information - Condensed Statements of Financial Condition (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets
Cash and due from banks	$ 120,792	$ 109,613	$ 301,373
Other assets	24,101	41,895
Total assets	7,516,154	5,416,006
Liabilities and Stockholders’ Equity
Borrowings	610,673	424,878
Other liabilities	37,488	35,233
Stockholder's equity	1,039,358	601,941	$ 571,903	$ 238,446
Total liabilities and stockholders’ equity	7,516,154	5,416,006
OceanFirst Financial Corp.
Assets
Cash and due from banks	3,930	16
Advances to subsidiary Bank	14,026	33,749
Investment securities	1,000	1,000
ESOP loan receivable	10,431	3,051
Investment in subsidiaries	1,107,539	619,253
Other assets	234	1,956
Total assets	1,137,160	659,025
Liabilities and Stockholders’ Equity
Borrowings	94,134	56,519
Other liabilities	3,668	565
Stockholder's equity	1,039,358	601,941
Total liabilities and stockholders’ equity	$ 1,137,160	$ 659,025