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Stock Options (Details) (2012 Plan Stock Options, USD $) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011
Stock option details |  |  |  |
Maximum exercisable period for options granted |  |  | 10 years |
Shares available for future grants | 800,000 |  | 800,000 |
Stock-based compensation expense | $ 113,000 | $ 85,000 | $ 366,000 | $ 280,000
Stock-based compensation cost, unrecognized, related to non-vested options | 947,000 |  | 947,000 |
Stock-based compensation cost, unrecognized, related to non-vested options, weighted-average period of recognition |  |  | 1 year 9 months 4 days |
Stock option activity |  |  |  |
Options outstanding at the beginning of the period (in shares) |  |  | 844,721 |
Less: |  |  |  |
Options exercised (in shares) |  |  | 4,165 |
Options forfeited (in shares) |  |  | 75,951 |
Options outstanding at the end of the period (in shares) | 764,605 |  | 764,605 |
Options fully vested and exercisable at the end of the period (in shares) | 396,303 |  | 396,303 |
Stock options, weighted average exercise price |  |  |  |
Options outstanding at the beginning, weighted average exercise price (in dollars per share) |  |  | $ 19.08 |
Less: |  |  |  |
Options exercised, weighted average exercise price (in dollars per share) |  |  | $ 10.40 |
Options forfeited, weighted average exercise price (in dollars per share) |  |  | $ 19.31 |
Options outstanding at the end, weighted average exercise price (in dollars per share) | $ 19.11 |  | $ 19.11 |
Options fully vested and exercisable at the end, weighted average exercise price (in dollars per share) | $ 23.82 |  | $ 23.82 |
Stock options, weighted average remaining contractual term |  |  |  |
Options outstanding at the end, weighted average remaining contractual term |  |  | 3 years 9 months 14 days |
Options fully vested and exercisable at the end, weighted average remaining contractual term |  |  | 1 year 10 months 17 days |
Stock options, aggregate intrinsic value |  |  |  |
Options outstanding at the end, aggregate intrinsic value | 2,478,000 |  | 2,478,000 |
Options fully vested and exercisable at the end, aggregate intrinsic value | $ 472,000 |  | $ 472,000 |
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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- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. + 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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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. + 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 (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(1)(f) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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