Borrowings - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Federal funds purchased	$ 101,600
Securities sold under agreements to repurchase	24,900
Securities sold under agreement to repurchase maturities due	$ 20,000
Borrowings maturity period	1 year
Repayment of borrowings		$ 20,000
Long-term debt prepayment fees	$ 0	2,828
Securities Sold under Agreements to Repurchase
Debt Instrument [Line Items]
Pledged securities	$ 58,200
Federal Home Loan Bank of New York
Debt Instrument [Line Items]
Long-term debt prepayment fees		638
Repayment of borrowings from the Federal Home Loan Bank		34,000
Debt Securities Sold Under Agreement To Repurchase
Debt Instrument [Line Items]
Long-term debt prepayment fees		$ 2,200

Long term debt prepayment fee.

No definition available.

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- Definition

Securities sold under agreement to repurchase maturities due.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ 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))
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- Definition

The cash outflow for the payment of loan drawn from Federal Home Loan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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- Definition

The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 05
-Paragraph 17
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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

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