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Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2017 USD ($) Incentive_Plan shares | Mar. 31, 2016 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of equity incentive plans | Incentive_Plan | 3 |
Stock options exercised, Shares | 0 | 35,679
Proceeds from stock option exercises | $ |  | $ 454
Share-based compensation expense | $ | $ 400 | 200
Restricted Stock Units (RSUs) [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Market value of restricted shares granted | $ |  | $ 900
Restricted Stock Units (RSUs) [Member] | Executive Officers [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted common stock granted |  | 16,687
Restricted Stock Units (RSUs) [Member] | Non-employee Directors [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted common stock granted |  | 376
2005 Incentive Plan [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Plan expiration date | Oct. 27, 2015 |
2012 Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted common stock granted | 0 |

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- Definition The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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