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Summary of Significant Accounting Policies - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended | 14 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 31, 2016 $ / shares shares | Mar. 31, 2016 USD ($) $ / shares shares | Feb. 28, 2015 USD ($) | Apr. 30, 2013 USD ($) | Dec. 31, 2011 $ / shares shares | Sep. 30, 2016 USD ($) Employees $ / shares shares | Jun. 30, 2016 USD ($) | Sep. 30, 2016 USD ($) Employees Segment $ / shares shares | Sep. 30, 2015 USD ($) | Dec. 31, 2014 USD ($) shares | Dec. 31, 2013 shares | Dec. 31, 2012 shares | Dec. 31, 2011 $ / shares shares | Aug. 31, 2014 USD ($) | Aug. 15, 2016 | May 06, 2016 shares | May 05, 2016 shares | Dec. 31, 2015 USD ($) shares | Apr. 30, 2015 $ / shares
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of segments | Segment |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of employees eliminated | Employees |  |  |  |  |  |  |  |  | 50 |  |  |  |  |  |  |  |  |  |  |  |  |
Wind-down expense | $ |  |  |  |  |  | $ 2,694 |  |  | $ 3,806,142 |  |  |  |  |  |  |  |  |  |  |  |  |
Accumulated deficit | $ |  |  |  |  |  | (467,980,451) |  |  | (467,980,451) |  |  |  |  |  |  |  |  |  |  | $ (456,686,634) |  |
Cash and cash equivalents | $ |  |  |  |  |  | $ 2,078,618 |  |  | $ 2,078,618 |  | $ 21,185,263 | $ 24,987,603 |  |  |  |  |  |  |  | $ 12,110,565 |  |
Number of existing employees after wind down of operations | Employees |  |  |  |  |  | 4 |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  | 200,000,000 | [1] |  | 200,000,000 | [1] |  |  |  |  |  |  |  | 200,000,000 | 225,000,000 | 200,000,000 | [1] |
Stockholders ownership after proposed merger |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.00% |  |  |  |  |
Minimum cash position required for completion of merger | $ |  |  |  |  |  | $ 0 |  |  | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity period for market accounts, money market funds and investments |  |  |  |  |  |  |  |  | 90 days |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | 651,902 |  | $ 770,964 | $ 651,902 |  |  |  |  |  |  |  |  |  |  | $ 770,964 |  |
Proceeds from issuance of stock units | $ |  |  |  |  |  |  |  |  | 7,259,613 |  | $ 24,942,963 |  |  |  |  |  |  |  |  |  |  |
Value of patent | $ |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |
Other Income | $ |  |  |  |  |  |  |  | 8,917,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of a loan | $ |  |  |  |  |  |  |  | 243,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accumulated other comprehensive income | $ |  |  |  |  |  | 47,386 |  |  | 47,386 |  |  |  |  |  |  |  |  |  |  | $ 47,359 |  |
Microbot Medical Ltd [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholders ownership after proposed merger |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 95.00% |  |  |  |  |
CIRM [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approval of fund by California Institute for Regenerative Medicine (CIRM) | $ |  |  |  | $ 19,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate proceeds from disbursement of the loan | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9,600,000 |  |  |  |  |  |
Forgiveness of loan principal | $ |  |  | $ 8,917,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrued interest forgiven | $ |  |  | 243,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayment of aggregate loan proceeds received | $ |  |  | $ 679,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Income | $ |  |  |  |  |  |  |  | 8,917,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of a loan | $ |  |  |  |  |  |  |  | 243,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series A Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares | $ 0.30 | $ 3.60 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of securities callable by each warrant or right warrants |  | 0.50 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants exercised | 1,187,190 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of additional warrants issued |  | 166,473 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants outstanding | 1,277,609 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | 115,000 |  |  | 115,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant expiration period |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series A Warrants [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8.40
Series B Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term of warrant |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares | $ 0.30 | $ 5.04 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of securities callable by each warrant or right warrants |  | 0.75 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of additional warrants issued |  | 249,709 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants outstanding | 1,916,407 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | 482,000 |  |  | 482,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant expiration period |  | 1 year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants surrendered | 1,546,360 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2011 Series A Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares | $ 0.30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants exercised | 531,814 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued upon warrants exercise | 531,814 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants outstanding | 578,081 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | $ 55,000 |  |  | $ 55,000 |  |  |  |  |  |  |  |  |  |  |  |  |
2016 Series A Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares | $ 0.30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants exercised | 1,187,190 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued upon warrants exercise | 1,187,190 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduced exercise price of Series A Warrants in exchange for surrender of Series B Warrants | $ / shares | $ 0.30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants outstanding | 1,277,609 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2016 Series B Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares | $ 0.30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants outstanding | 1,916,407 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants surrendered | 1,546,360 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
December 2011 Financing [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of securities callable by each warrant or right warrants |  |  |  |  | 1 | 1 |  |  | 1 |  |  |  |  |  | 1 |  |  |  |  |  |  |
Number of shares issued upon warrants exercise |  |  |  |  |  |  |  |  |  |  |  |  |  | 225,000 |  |  |  |  |  |  |  |
December 2011 Financing [Member] | Series A Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term of warrant |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of securities callable by warrants |  |  |  |  | 666,667 |  |  |  |  |  |  |  |  |  | 666,667 |  |  |  |  |  |  |
Number of securities callable by each warrant or right warrants |  |  |  |  |  | 1 |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants exercised |  |  |  |  |  |  |  |  |  |  |  | 98,335 | 32,045 | 183,215 |  |  |  |  |  |  |  |
Number of additional warrants issued |  |  |  |  |  |  |  |  |  |  |  |  |  | 225,000 |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | $ 54,945 |  | $ 770,964 | $ 54,945 |  |  |  |  |  |  |  |  |  |  |  |  |
December 2011 Financing [Member] | Series A Warrants [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares |  |  |  |  | $ 16.80 |  |  |  |  |  |  |  |  |  | $ 16.80 |  |  |  |  |  |  |
Number of shares issued upon warrants exercise |  |  |  |  |  |  |  |  |  |  |  | 98,335 | 32,045 | 183,215 |  |  |  |  |  |  |  |
December 2011 Financing [Member] | Series B Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term of warrant |  |  |  |  | 90 days |  |  |  |  |  |  |  |  |  | 90 days |  |  |  |  |  |  |
Number of securities callable by warrants |  |  |  |  | 666,667 |  |  |  |  |  |  |  |  |  | 666,667 |  |  |  |  |  |  |
Exercise price of warrants | $ / shares |  |  |  |  | $ 15.00 |  |  |  |  |  |  |  |  |  | $ 15.00 |  |  |  |  |  |  |
Number of warrants exercised |  |  |  |  |  |  |  |  |  |  |  |  |  | 225,000 |  |  |  |  |  |  |  |
Number of warrants expired |  |  |  |  |  |  |  |  | 441,667 |  |  |  |  | 441,667 |  |  |  |  |  |  |  |
April 2015 Financing [Member] | Series A Warrants [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares |  | $ 6.24 |  |  |  | $ 6.24 |  |  | $ 6.24 |  |  |  |  |  |  |  |  |  |  |  |  | $ 8.40
March 2016 Financing [Member] | Series A Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | $ 114,918 |  |  | $ 114,918 |  |  |  |  |  |  |  |  |  |  |  |  |
March 2016 Financing [Member] | Series A Warrants [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price of warrants | $ / shares |  | $ 3.60 |  |  |  | $ 3.60 |  |  | $ 3.60 |  |  |  |  |  |  |  |  |  |  |  |  |
March 2016 Financing [Member] | Series B Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of warrant liability | $ |  |  |  |  |  | $ 482,039 |  |  | $ 482,039 |  |  |  |  |  |  |  |  |  |  |  |  |
Underwritten Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued upon warrants exercise |  | 2,222,250 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of stock units | $ |  | $ 8,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of stock units issued, price per share | $ / shares |  | $ 3.60 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Over-Allotment-Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of securities callable by each warrant or right warrants |  | 416,672 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued upon warrants exercise |  | 333,338 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Underwriting option exercise period |  | 45 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | Adjusted for the 1-for-12 reverse stock split as discussed in Note 1.

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