Borrowed Funds - Summary of Borrowed Funds (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Oct. 17, 2013
Banking and Thrift [Abstract]
Federal Home Loan Bank advances, Amount	$ 305,238	$ 175,000
Securities sold under agreements to repurchase, Amount	67,812	68,304
Other borrowings, Amount	27,500us-gaap_OtherBorrowings	27,500us-gaap_OtherBorrowings
Borrowed funds, Amount	$ 400,550us-gaap_DebtAndCapitalLeaseObligations	$ 270,804us-gaap_DebtAndCapitalLeaseObligations
Federal Home Loan Bank advances, Weighted Average Rate	1.18%	0.69%	2.31%
Securities sold under agreements to repurchase, Weighted Average Rate	0.12%	0.15%
Other borrowings, Weighted Average Rate	2.75%ocfc_OtherBorrowingsWeightedAverageRate	2.76%ocfc_OtherBorrowingsWeightedAverageRate
Borrowed funds, Weighted Average Rate	1.11%	0.76%

Other Borrowings Weighted Average Rate

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- Definition

Securities Sold Under Repurchase Agreements Weighted Average Interest Rate

+ References

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

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- Definition

States the weighted average interest rate applicable to the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

+ References

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- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

No definition available.

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(1))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Section 50

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-Section 55

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-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226008-175313

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 1

-Article 9

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-Name Accounting Standards Codification

-Topic 235

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(m)(1)(a)(i))

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