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Stock Options (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015 | Apr. 05, 2012
Stock options under 2012 Plan |  |  |
Stock option details |  |  |
Shares available for future grants | 186,250 |  | 800,000
Maximum exercisable period for options granted | 10 years |  |
Stock option activity |  |  |
Options outstanding at the beginning of the period (in shares) | 871,727 |  |
Plus: Options granted (in shares) | 4,000 |  |
Less: |  |  |
Options exercised (in shares) | 9,725 |  |
Options forfeited (in shares) | 14,000 |  |
Options outstanding at the end of the period (in shares) | 852,002 |  |
Options fully vested and exercisable at the end of the period (in shares) | 251,983 |  |
Stock options, weighted average exercise price |  |  |
Options outstanding at the beginning, weighted average exercise price (in dollars per share) | $ 19.08 |  |
Plus: Options granted, weighted average exercise price (in dollars per share) | 22.07 |  |
Less: |  |  |
Options exercised, weighted average exercise price (in dollars per share) | 11.55 |  |
Options expired, weighted average exercise price (in dollars per share) | 0.00 |  |
Options forfeited, weighted average exercise price (in dollars per share) | 20.97 |  |
Options outstanding at the end, weighted average exercise price (in dollars per share) | 19.15 |  |
Options fully vested and exercisable at the end, weighted average exercise price (in dollars per share) | $ 15.53 |  |
Stock options, weighted average remaining contractual term |  |  |
Options outstanding at the end, weighted average remaining contractual term | 6 years 5 months 16 days |  |
Options fully vested and exercisable at the end, weighted average remaining contractual term | 4 years 1 month 13 days |  |
Stock options, aggregate intrinsic value |  |  |
Options outstanding at the end, aggregate intrinsic value | $ 4,699,000 |  |
Options fully vested and exercisable at the end, aggregate intrinsic value | 2,299,000 |  |
Stock-based compensation expense | 285,000 | $ 292,000 |
Stock-based compensation cost, unrecognized, related to non-vested options | $ 3,078,000 |  |
Stock-based compensation cost, unrecognized, related to non-vested options, weighted-average period of recognition | 2 years |  |
Incentive stock options granted to 10% shareholders |  |  |
Stock option details |  |  |
Maximum exercisable period for options granted | 5 years |  |

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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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