Fair Value Measurements - Schedule of Balances of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Securities available for sale:
Securities available-for-sale	$ 59,825	$ 42,604
Mortgage servicing rights	658	596
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	2,806	2,897
Corporate Bonds
Securities available for sale:
Securities available-for-sale	3,945
US Government Agencies
Securities available for sale:
Securities available-for-sale	21,288	16,965
State and Municipal Obligations
Securities available for sale:
Securities available-for-sale	28,857	23,401
Certificates of Deposit
Securities available for sale:
Securities available-for-sale	5,735	2,238
Cash and Cash Equivalents
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	3	4
Fixed Income Funds
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	1,119	1,139
Equity Funds
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	1,684	1,754
Fair Value, Inputs, Level 1
Securities available for sale:
Securities available-for-sale	1,216	845
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	2,806	2,897
Fair Value, Inputs, Level 1 \| US Government Agencies
Securities available for sale:
Securities available-for-sale	1,216	845
Fair Value, Inputs, Level 1 \| Cash and Cash Equivalents
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	3	4
Fair Value, Inputs, Level 1 \| Fixed Income Funds
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	1,119	1,139
Fair Value, Inputs, Level 1 \| Equity Funds
Defined benefit plan assets:
Defined Benefit Plan Fair Value Of Plan Assets	1,684	1,754
Fair Value, Inputs, Level 2
Securities available for sale:
Securities available-for-sale	54,416	41,759
Fair Value, Inputs, Level 2 \| US Government Agencies
Securities available for sale:
Securities available-for-sale	20,072	16,120
Fair Value, Inputs, Level 2 \| State and Municipal Obligations
Securities available for sale:
Securities available-for-sale	28,857	23,401
Fair Value, Inputs, Level 2 \| Certificates of Deposit
Securities available for sale:
Securities available-for-sale	5,487	2,238
Fair Value, Inputs, Level 3
Securities available for sale:
Securities available-for-sale	4,193
Mortgage servicing rights	658	$ 596
Fair Value, Inputs, Level 3 \| Corporate Bonds
Securities available for sale:
Securities available-for-sale	3,945
Fair Value, Inputs, Level 3 \| Certificates of Deposit
Securities available for sale:
Securities available-for-sale	$ 248

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122625-111746

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