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Stock-Based Compensation - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2013 | 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 grants | 0 | 0 | 0 | 0 | 0
Stock option or restricted stock grants under 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 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 | 384,000 |  |  |  |
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 | 400,000 |  |  |  |
Intrinsic value of all stock options outstanding and exercisable | 100,000 |  |  |  |
Maximum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock options granted to employees under 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 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 |  |  |  |
Stock Options [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock options granted to employees under 2000, and 2004 Employee Stock Option Plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, expiration period | 7 years |  |  |  |
Stock option or restricted stock grants under 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 2 years |  |  |  |
Director Stock Option Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock options granted to employees under 2000, and 2004 Employee Stock Option Plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, expiration period | 10 years |  |  |  |
Stock option or restricted stock grants under 2000 and 2004 Employee stock option plans, Independent Director Stock Option Plan, and Stock Incentive Plan of 2006, vesting period | 5 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 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 equity grants in 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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- Definition Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation. + References No definition available. + Details
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- Definition Unrecognized cost of unvested options awarded to employees as compensation. + 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 Period from grant date that an equity-based award expires, 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)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- 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 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 value. + References No definition available. + Details
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