Fair Value Measurements - Book Value and Estimated Fair Value of Bank's Significant Financial Instruments Not Recorded at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financial Assets:
Securities held-to-maturity	$ 474,215	$ 495,082
Financial Liabilities:
Time deposits	207,218us-gaap_TimeDeposits	217,943us-gaap_TimeDeposits
Securities sold under agreements to repurchase with retail customers	67,812	68,304
Book Value [Member]
Financial Assets:
Cash and due from banks	36,117	33,958
Securities held-to-maturity	469,417	495,599
Federal Home Loan Bank of New York stock	19,170	14,518
Loans receivable and mortgage loans held-for-sale	1,693,047	1,542,245
Financial Liabilities:
Deposits other than time deposits	1,512,917	1,528,820
Time deposits	207,218	217,943
Securities sold under agreements to repurchase with retail customers	67,812	68,304
Federal Home Loan Bank advances and other borrowings	332,738	202,500
Level 1 Inputs [Member]
Financial Assets:
Cash and due from banks	36,117	33,958
Financial Liabilities:
Securities sold under agreements to repurchase with retail customers	67,812	68,304
Level 2 Inputs [Member]
Financial Assets:
Securities held-to-maturity	474,215	493,432
Financial Liabilities:
Deposits other than time deposits	1,512,917	1,528,820
Time deposits	208,651	220,409
Federal Home Loan Bank advances and other borrowings	332,432	201,393
Level 3 Inputs [Member]
Financial Assets:
Securities held-to-maturity		1,650
Federal Home Loan Bank of New York stock	19,170	14,518
Loans receivable and mortgage loans held-for-sale	$ 1,709,819	$ 1,561,208

Deposits Other Than Time Deposits Fair Value Disclosure

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Name Accounting Standards Codification

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investments in debt securities classified as held-to-maturity.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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-Topic 325

-SubTopic 20

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

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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.

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-Publisher FASB

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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(1))

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-Number 210

-Section 03

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-Article 9

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-Topic 235

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

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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