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Stock Options and Restricted Stock - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) Companies shares | Dec. 31, 2014 USD ($) shares | Dec. 31, 2013 USD ($) shares | Dec. 31, 2012 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Total tax expense | $ | $ 2,203,000 | $ 2,841,000 | $ 2,024,000 |
2005 Incentive Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock options exercise price | 100.00% |  |  |
Company's voting stock | 10.00% |  |  |
Stock options exercise price | 110.00% |  |  |
Duration for Stock option grants exercisable | 10 years |  |  |
Stock options exercise period | 5 years |  |  |
Expiration of stock option | 90 days |  |  |
Unexercised portion of stock option remains exercisable | 1 year |  |  |
Number of companies used for the estimation of expected volatility | Companies | 6 |  |  |
Dividend yield assumed | 0.00% |  |  |
Cash dividends paid | $ |  |  | 0 |
Compensation expense | $ | $ 100,000 | 300,000 | $ 300,000 |
Total tax expense | $ | $ 81,000 | $ 38,000 |  |
Restricted stock outstanding | 1,600 | 2,400 | 6,400 | 8,000
2010 Restricted Stock Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Compensation expense | $ | $ 300,000 | $ 200,000 | $ 200,000 |
Total tax expense | $ | $ 13,000 | 7,000 | $ 18,000 |
Shares authorized under incentive plan | 100,000 |  |  |
Common stock available for future awards | 26,074 |  |  |
Restricted stock award for a number of shares | $ | $ 45,000 | $ 30,000 |  |
Restricted stock outstanding | 7,112 | 5,229 | 5,376 | 7,833
Restricted stock granted | 7,112 | 5,229 | 5,376 |
2010 Restricted Stock Plan [Member] | Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Additional restricted stock award for a number of shares | 15,000 |  |  |
2012 Equity and Incentive Compensation Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Shares authorized under incentive plan | 500,000 |  |  |
Common stock available for future awards | 380,935 |  |  |
Restricted stock granted | 50,461 |  |  |
2012 Equity and Incentive Compensation Plan [Member] | Share Based Grants [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Compensation expense | $ | $ 600,000 | $ 600,000 | $ 300,000 |
2012 Equity and Incentive Compensation Plan [Member] | Long-Term Incentive Awards [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Compensation expense | $ | $ 200,000 | $ 400,000 | $ 600,000 |
2012 Equity and Incentive Compensation Plan [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Restricted stock granted |  | 4,312 |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
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