Borrowings - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Short-term Debt [Line Items]
Federal home loan bank additional borrowings capacity	$ 60,600	$ 58,300
Loans Pledged as Collateral	122,100	122,800
Cash management lines of credit, additional borrowings	15,000	15,000
Securities Sold under Agreements to Repurchase	5,700	$ 5,691	$ 5,098
Security Owned and Pledged as Collateral, Fair Value	$ 8,500
Federal Home Loan one
Short-term Debt [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate, Range from	3.08%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate, Range to	6.65%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Weighted Average Interest Rate	3.80%
Federal Home Loan two
Short-term Debt [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate, Range from		3.08%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate, Range to		6.65%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Weighted Average Interest Rate		3.81%

Cash management lines of credit, additional borrowings.

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- Definition

Federal home loan bank additional borrowings capacity.

+ References

No definition available.

+ Details

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- Definition

Discloses the lowest interest rate applicable to any of the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ 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(3)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Discloses the highest interest rate applicable to any of the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

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- Definition

Describes the weighted average interest rate applicable to the specific advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
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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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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Repurchase Agreement Accounted for as a Collateralized Borrowing
-URI http://asc.fasb.org/extlink&oid=49203159

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

+ 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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