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Shared-Based Payments - Additional Information (Detail) (USD $) | 0 Months Ended | 12 Months Ended | 60 Months Ended |  |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended
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Mar. 16, 2011 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Feb. 28, 2003 | Mar. 16, 2011 Stock Option One [Member] Original Options [Member] | Mar. 16, 2011 Stock Option Two [Member] Original Options [Member] | Dec. 31, 2013 Stock Option Plan 2000 [Member] | Dec. 31, 2013 Two Thousand and Three Stock Option Plan [Member] | Dec. 31, 2013 Two Thousand and Thirteen Stock Incentive Plan [Member] | Oct. 31, 2013 Two Thousand and Thirteen Stock Incentive Plan [Member] | Dec. 31, 2013 Equity Incentive Plan 2003 [Member] | Dec. 31, 2013 Maximum [Member] Equity Incentive Plan 2003 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate of shares |  |  |  |  |  | 2,051,644 |  |  | 130,725 |  |  | 1,960,168 |  |
Increase in aggregate of shares |  |  | 4,336,730 |  | 3,790,760 |  |  |  | 150,297 |  |  |  |  |
Common stock share outstanding |  | 3,200,958 | 3,249,541 |  |  |  |  |  | 23,657 | 2,559,011 | 618,290 |  |  |
weighted average exercise price | $ 0.94 | $ 4.90 | $ 0.94 |  |  |  | $ 1.88 | $ 4.69 | $ 0.83 | $ 1.52 | $ 19.06 |  |  |
Common Stock |  |  | 545,970 |  | 1,739,116 |  |  |  |  |  |  |  |  |
Percentage of Common stock share outstanding |  |  |  |  |  |  |  |  |  |  | 4.00% |  |  |
Description of exchange ratio of original options with replacement options | one-for-one basis |  |  |  |  |  |  |  |  |  |  |  |  |
Total original Options exchanged for replacement Options |  | 1,921,894 |  |  |  |  |  |  |  |  |  |  |  |
Options granted, maximum term |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years
Expected life of option term |  | 7 years | 7 years | 7 years |  |  |  |  |  |  |  |  | 7 years |
Common stock, shares issued |  | 1,268,049 | 863,176 | 49,883 |  |  |  |  |  |  |  |  |  |
Cash proceeds from exercise of stock options |  | $ 1,100,000 | $ 46,826 | $ 53,225 |  |  |  |  |  |  |  |  |  |
Weighted-average grant-date fair value of options granted |  | $ 6.91 | $ 0.94 | $ 0.94 |  |  |  |  |  |  |  |  |  |
Aggregate intrinsic value of options exercised |  | 5,400,000 | 271,929 | 102,418 |  |  |  |  |  |  |  |  |  |
Fair value of shares vested |  | 487,603 | 879,024 | 1,108,107 |  |  |  |  |  |  |  |  |  |
Unrecognized compensation cost related to non-vested stock-based compensation arrangements |  | $ 7,600,000 |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized compensation expense recognition period |  | 4 years |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 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 The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585 + 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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- Definition Expected term of share-based compensation awards, 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 S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section D -Subsection 2 + 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 Number of options outstanding, including both vested and non-vested options. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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