Acquisitions - Additional Information (Detail) - Eagle National Bancorp, Inc [Member] $ in Thousands	Dec. 04, 2015 USD ($) Branch
Business Acquisition [Line Items]
Date of acquisition	Dec. 04, 2015
Number of branches acquired \| Branch	5
Total purchase price related to acquisition	$ 24,655
Acquired credit impaired loans	3,500
Credit impaired loans, nonaccretable difference amount	2,000
Loan portfolio without evidence of deterioration	120,700
Fair value of loan portfolio	$ 121,400

Business acquisition credit impaired loans purchased.

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- Definition

Business acquisition loan portfolio acquired carrying value.

+ References

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- Definition

Business acquisition loan portfolio acquired fair value.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

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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

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

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- Definition

The number of businesses acquired by the entity during the period.

+ References

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