Loans Receivable, Net - Summary of Loans Receivable (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Real estate mortgage	$ 1,435,392ocfc_LoansAndLeasesReceivableRealEstate	$ 1,310,351ocfc_LoansAndLeasesReceivableRealEstate
Consumer	199,349	200,683
Commercial and industrial	83,946	60,545
Total loans	1,718,687	1,571,579
Loans in process	(16,731)	(12,715)
Deferred origination costs, net	3,207	3,526
Allowance for loan losses	(16,317)	(20,930)	(20,510)	(18,230)
Loan adjustments	(29,841)	(30,119)
Loans receivable, net	1,688,846	1,541,460
One-to-Four Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Real estate mortgage	737,889	750,585
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Real estate mortgage	649,951	528,945
Total loans	649,951	528,945
Allowance for loan losses	(8,935)	(10,371)	(8,937)
Residential Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Real estate mortgage	$ 47,552	$ 30,821

Loans And Leases Deferred Origination Costs

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Loans And Leases Receivable Real Estate

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- Definition

Amount of other addition (reduction) in allowance reserve for credit loss.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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-Number Topic 6

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Amount before allowance of commercial loans and leases receivable includes, but not limited to, commercial and industrial loans, agricultural loans, mortgage loans, promissory notes, interbank and other loans to financial institutions, draws against credit facilities, trade financing, lease financings. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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-Publisher FASB

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Amount before allowance of consumer loans, including, but not limited to, mortgage, home equity, vehicles, credit card, installment, and lease financing. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of undisbursed portion of the loan receivable balance (loans in process). Excludes loans and leases covered under loss sharing agreements.

+ References

No definition available.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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