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Stock Based Compensation (Details) (USD $) | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Stock options granted (in shares) |  |  |  |  | 18,000 |  | 12,000 |  |  |
Stock options granted (in dollars per share) |  |  |  |  | $ 2.79 |  | $ 5.50 |  |  |
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract] |  |  |  |  |  |  |  |  |  |
Stock options outstanding (in shares) | 390,800 | [1] | 534,900 | [1] | 390,800 | [1] | 534,900 | [1] | 528,800 | 607,967
Outstanding and fully vested stock options (in shares) | 352,800 | [1] | 432,900 | [2] | 352,800 | [1] | 432,900 | [2] |  |
Weighted average exercise price (in dollars per share) | $ 9.66 | [1] | $ 9.85 | [1] | $ 9.66 | [1] | $ 9.85 | [1] | $ 9.82 | $ 9.89
Compensation expense | $ 26,000 |  | $ 38,000 |  | $ 79,000 |  | $ 135,000 |  |  |
Total unrecognized compensation cost related to unvested options | 104,000 |  |  |  | 104,000 |  |  |  |  |
Unrecognized compensation cost to be recognized in 2013 | 40,000 |  |  |  | 40,000 |  |  |  |  |
Unrecognized compensation cost to be recognized in 2014 | 64,000 |  |  |  | 64,000 |  |  |  |  |
Contractual Term With One-third Yearly Vesting [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Contractual term |  |  |  |  | 6 years |  |  |  |  |
Vesting period |  |  |  |  | 3 years |  |  |  |  |
Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract] |  |  |  |  |  |  |  |  |  |
Stock options outstanding (in shares) | 227,600 |  |  |  | 227,600 |  |  |  |  |
Outstanding and fully vested stock options (in shares) | 207,600 |  |  |  | 207,600 |  |  |  |  |
Weighted average exercise price (in dollars per share) | $ 10.03 |  |  |  | $ 10.03 |  |  |  |  |
Remaining weighted contractual life |  |  |  |  | 1 year 6 months |  |  |  |  |
Compensation expense | 22,000 |  | 34,000 |  | 58,000 |  | 106,000 |  |  |
Employee Stock Option [Member] | Contractual Term With One-fifth Yearly Vesting [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Contractual term |  |  |  |  | 10 years |  |  |  |  |
Vesting period |  |  |  |  | 5 years |  |  |  |  |
Director Stock Options [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Contractual term |  |  |  |  | 10 years |  |  |  |  |
Vesting period |  |  |  |  | 6 months |  |  |  |  |
Stock options granted (in shares) |  |  |  |  | 18,000 |  |  |  |  |
Number of directors re-elected |  |  |  |  | 5 |  |  |  |  |
Number of new directors elected |  |  |  |  | 1 |  |  |  |  |
Stock options granted (in dollars per share) |  |  |  |  | $ 2.79 |  |  |  |  |
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract] |  |  |  |  |  |  |  |  |  |
Weighted-average fair value per share (in dollars per share) |  |  |  |  | $ 1.96 |  | $ 3.55 |  |  |
Risk -free interest rate (in hundredths) |  |  |  |  | 2.92% |  | 1.75% |  |  |
Expected volatility of stock (in hundredths) |  |  |  |  | 58.88% |  | 56.74% |  |  |
Dividend yield (in hundredths) |  |  |  |  | 0.00% |  | 0.00% |  |  |
Expected option life |  |  |  |  | 10 years |  | 10 years |  |  |
Stock options outstanding (in shares) | 163,200 |  |  |  | 163,200 |  |  |  |  |
Outstanding and fully vested stock options (in shares) | 145,200 |  |  |  | 145,200 |  |  |  |  |
Weighted average exercise price (in dollars per share) | $ 10.22 |  |  |  | $ 10.22 |  |  |  |  |
Remaining weighted contractual life |  |  |  |  | 4 years 9 months 18 days |  |  |  |  |
Compensation expense | $ 4,000 |  | $ 4,000 |  | $ 21,000 |  | $ 29,000 |  |  |
[1] | Options with exercise prices ranging from $5.50 to $14.75
[2] | Options with exercise prices ranging from $7.05 to $14.75

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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 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64 -Subparagraph b -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. Reference 3: 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=6793087&loc=d3e301413-122809 Reference 4: 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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph g(1) -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. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + 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 (f)(2)(iii) -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 e(2)(c) -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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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + 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 (f)(2)(ii) -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 e(2)(b) -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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