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Subsequent Events - Additional Information (Detail) (USD $) | 0 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 0 Months Ended | 9 Months Ended | 0 Months Ended | 12 Months Ended | 0 Months Ended
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Oct. 22, 2013 | May 27, 2013 | Sep. 30, 2014 | Dec. 31, 2013 | Dec. 31, 2013 West Crest Limited [Member] | Sep. 30, 2014 Restricted Shares [Member] | Dec. 31, 2013 Restricted Shares [Member] | May 08, 2014 2013 Plan [Member] Restricted Shares [Member] Employees [Member] | Sep. 30, 2014 2013 Plan [Member] Restricted Shares [Member] Employees [Member] | Oct. 09, 2014 2013 Plan [Member] Restricted Shares [Member] Employees [Member] Subsequent Event [Member] | Dec. 31, 2013 2011 Plan [Member] Employee Stock Option [Member] January 16, 2014 [Member] Employees [Member] Vesting Period From January 1, 2015 To January 1, 2018 [Member] | Dec. 31, 2013 2011 Plan [Member] Employee Stock Option [Member] January 16, 2014 [Member] Employees [Member] Vesting Period From January 16, 2014 To January 16, 2017 [Member] | Jan. 16, 2014 2011 Plan [Member] Employee Stock Option [Member] January 16, 2014 [Member] Employees [Member] Subsequent Event [Member] | Jan. 16, 2014 2011 Plan [Member] Employee Stock Option [Member] January 16, 2014 [Member] Employees [Member] Subsequent Event [Member] Vesting Period From January 1, 2015 To January 1, 2018 [Member] | Jan. 16, 2014 2011 Plan [Member] Employee Stock Option [Member] January 16, 2014 [Member] Employees [Member] Subsequent Event [Member] Vesting Period From January 16, 2014 To January 16, 2017 [Member]
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of options, Granted | 228,000 | 560,000 | 177,600 |  |  |  |  |  |  |  |  |  | 177,600 | 120,000 | 57,600
Weighted average exercise price, Granted | $ 2.20 | $ 2.20 | $ 2.20 |  |  |  |  |  |  |  |  |  | $ 2.20 |  |
Contractual term |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |
Award vesting period |  |  |  |  |  |  |  |  | All five tranches will vest over a period of four years, with 25% of the awards vesting on various dates ranging from March 14, 2015 to May 13, 2015, with the remainder of the awards vesting on an annual basis thereafter. |  | January 1, 2015 to January 1, 2018, with 25% of the awards vesting on January 1, 2015 and the remainder of the awards vesting on an annual basis each January 1, thereafter | January 16, 2014 to January 16, 2017, with 25% of the awards vesting on January 16, 2014 and the remainder of the awards vesting on an annual basis each January 16, thereafter |  |  |
Percentage of awards vesting |  |  |  |  |  |  |  |  | 25.00% |  |  |  | 25.00% |  |
Payment date of outstanding payable |  |  |  |  | Jan. 29, 2014 |  |  |  |  |  |  |  |  |  |
Company name change date |  |  |  | Mar. 31, 2014 |  |  |  |  |  |  |  |  |  |  |
Number of shares, Granted |  |  |  |  |  | 100,000 | 400,000 | 100,000 |  | 406,000 |  |  |  |  |

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- Definition Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date. + 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 number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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)(2)(iii)(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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