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Stock-Based Compensation (Details Textual) (USD $) | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock option or restricted stock grants under 1997, 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 1 year |  |  |
Stock options granted to employees under 1997, 2000, and 2004 Employee Stock Option Plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, expiration period | 7 years |  |  |
Unrecognized compensation cost related to unvested stock options granted under various stock-based compensation plans | $ 0 |  |  |
Total unrecognized compensation costs relating to unvested restricted stock granted under Stock Incentive Plan of 2006 | 900,000 |  |  |
Stock-Based Compensation (Textual) [Abstract] |  |  |  |
Stock option or restricted stock grants |  | 0 | 0 | 0
Stock options granted to non-executive officers during 2005 | 3 weeks |  |  |
Stock options granted to non-employee directors under Independent Director Stock Option Plan, purchase price as a percentage of market price on date of grant | 125.00% |  |  |
Number of shares authorized for future incentive awards under our Stock Incentive Plan of 2006 | 366,000 |  |  |
Stock option grants, number of shares | 0 | 0 | 0 |
Weighted-average period for recognizing compensation costs related to unvested restricted stock granted under our Stock Incentive Plan of 2006 | 1 year |  |  |
Intrinsic value of all stock options outstanding and exercisable | 200,000 |  |  |
Maximum [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock options granted to employees under 1997, 2000, and 2004 Employee Stock Option Plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, expiration period | 10 years |  |  |
Restricted stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock option or restricted stock grants under 1997, 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 4 years |  |  |
Payments received from employees for restricted stock awards | $ 0 |  |  |
Director Stock Option Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock option or restricted stock grants under 1997, 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 5 years |  |  |
Stock options granted to employees under 1997, 2000, and 2004 Employee Stock Option Plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, expiration period | 10 years |  |  |
Director Stock Option Plan [Member] | Restricted stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock option or restricted stock grants under 1997, 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 2 years |  |  |
Stock Incentive Plan of 2006 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock option or restricted stock grants under 1997, 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 2 years |  |  |

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- Definition Payment required from employee for restricted stock awards. + References No definition available. + Details
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- Definition Share based compensation arrangement by share based payment award to non executive officers vesting period. + References No definition available. + Details
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- Definition Share based compensation arrangement by share based payment award expiration period. + References No definition available. + Details
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- Definition Share based payment award options outstanding and exercisable intrinsic value. + References No definition available. + Details
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- Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest. + References No definition available. + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph a -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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Purchase price of common stock expressed as a percentage of its fair market value. + References No definition available. + Details
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