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	Mar. 31, 2014	Dec. 31, 2013
Financial Assets:
Securities held-to-maturity	$ 498,383	$ 495,082
Financial Liabilities:
Securities sold under agreements to repurchase with retail customers	66,226	68,304
Book Value [Member]
Financial Assets:
Cash and due from banks	36,746	33,958
Securities held-to-maturity	496,111	495,599
Federal Home Loan Bank of New York stock	17,011	14,518
Loans receivable and mortgage loans held for sale	1,572,122	1,542,245
Financial Liabilities:
Deposits other than time deposits	1,504,587	1,528,820
Time deposits	215,544	217,943
Securities sold under agreements to repurchase with retail customers	66,226	68,304
Federal Home Loan Bank advances and other borrowings	259,800	202,500
Level 1 Inputs [Member]
Financial Assets:
Cash and due from banks	36,746	33,958
Securities held-to-maturity
Federal Home Loan Bank of New York stock
Loans receivable and mortgage loans held for sale
Financial Liabilities:
Deposits other than time deposits
Time deposits
Securities sold under agreements to repurchase with retail customers	66,226	68,304
Federal Home Loan Bank advances and other borrowings
Level 2 Inputs [Member]
Financial Assets:
Cash and due from banks
Securities held-to-maturity	496,997	493,432
Federal Home Loan Bank of New York stock
Loans receivable and mortgage loans held for sale
Financial Liabilities:
Deposits other than time deposits	1,504,587	1,528,820
Time deposits	217,689	220,409
Securities sold under agreements to repurchase with retail customers
Federal Home Loan Bank advances and other borrowings	258,691	201,393
Level 3 Inputs [Member]
Financial Assets:
Cash and due from banks
Securities held-to-maturity	1,386	1,650
Federal Home Loan Bank of New York stock	17,011	14,518
Loans receivable and mortgage loans held for sale	1,590,045	1,561,208
Financial Liabilities:
Deposits other than time deposits
Time deposits
Securities sold under agreements to repurchase with retail customers
Federal Home Loan Bank advances and other borrowings

Deposits Other Than Time Deposits Fair Value Disclosure

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- Definition

Time Deposits Fair Value Disclosure

+ References

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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

-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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- Definition

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

+ References

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

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-SubTopic 10

-Section 50

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-Subparagraph (f)

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-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (a)

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=29638263&loc=d3e39828-111592

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(1))

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-Paragraph 3

-Subparagraph (c)

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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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-SubTopic 20

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-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

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

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