Short-Term Borrowings - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Short-term Debt [Line Items]
Short-term borrowings, Total	$ 7,354,000	$ 436,000
Maturity period of federal funds	30 days
Federal funds purchased	$ 0	0
Available fund lines from correspondent banks	18,800,000	18,800,000
Securities sold under repurchase agreements	400,000	400,000
Short-term FHLB advances, Total	$ 7,000,000	$ 0
Minimum [Member]
Short-term Debt [Line Items]
Maturity period of federal funds	1 day
Maximum [Member]
Short-term Debt [Line Items]
Maturity period of federal funds	4 days

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

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
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-Name Accounting Standards Codification
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Subparagraph (c)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Subparagraph (SX 210.4-08.(m)(1)(a)(i))
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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

+ Details

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
-Subparagraph 2, 3
-Article 9

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No definition available.

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- Definition

Available fund lines from correspondent banks.

+ References

No definition available.

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- Definition

Maturity period of federal funds.

+ References

No definition available.

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