| Stockholders' Equity - Additional Information (Detail) - USD ($)
 |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |  |  | 
| Oct. 13, 2015 | Jul. 15, 2015 | Jun. 01, 2015 | Nov. 06, 2014 | Jun. 02, 2014 | Dec. 02, 2015 | Sep. 18, 2015 | Aug. 31, 2015 | Jul. 28, 2015 | Dec. 01, 2014 | Dec. 02, 2013 | Jun. 30, 2013 | May. 31, 2013 | Mar. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Oct. 19, 2015 | Jun. 02, 2015 | Dec. 02, 2014 | Mar. 17, 2014 | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Based compensation, Options Contractual term |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  | 
| Stock-based compensation weighted-average vesting period |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 month 6 days |  |  |  |  |  |  | 
| Employee Stock Purchase Plan to eligible employees, Reckoning fair value percentage during offering period |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 85.00% |  |  |  |  |  |  | 
| Employee Stock Purchase Plan to eligible employees, compensation expense recognized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 27,000 | $ 25,000 | $ 46,000 |  |  |  |  | 
| Share Based Compensation Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,900,000 | $ 4,000,000 | 66,000 |  |  |  |  | 
| Common Stock Par Or Stated Value Per Share |  |  |  |  |  |  | $ 0.0001 |  |  |  |  |  |  |  | $ 0.001 | $ 0.001 |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 11,600,000 |  |  |  |  |  | 
| Share Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2.93 |  |  |  |  |  |  | 
| Research And Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 18,402,000 | 10,239,000 | 25,682,000 |  |  |  |  | 
| General And Administrative Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 21,584,000 | 10,413,000 | 10,098,000 |  |  |  |  | 
| Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,000,000 | $ 3,300,000 |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8,660,280 |  |  |  |  |  |  | 
| Fair Value Assumptions, Weighted Average Volatility Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.60% |  |  |  |  |  |  | 
| Proceeds from Stock Options Exercised |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 216,000 | 596,000 | 970,000 |  |  |  |  | 
| Fair Value Assumption Historical Volatility Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 80.00% |  |  |  |  |  |  | 
| Fair Value Assumptions Implied Volatility Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.00% |  |  |  |  |  |  | 
| Class of Warrant or Right, Exercise Price of Warrants or Rights |  |  |  |  |  |  | $ 7.00 |  |  |  |  |  |  |  | $ 2,500 |  |  |  |  |  |  | 
| Stock Issued During Period, Value, Issued for Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000 | 4,000 | 4,000 |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,500,000 | 0 |  |  |  |  |  |  | 
| Class of Warrant or Right, Number of Securities Called by Warrants or Rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.00 |  |  |  |  |  |  | 
| Fair Value Assumptions, Risk Free Interest Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.10% |  |  |  |  |  |  | 
| Proceeds from issuance of Common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | 3,502,000 | 91,337,000 |  |  |  |  | 
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000 |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,700,000 |  |  |  |  |  |  | 
| Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 14,291,000 | 5,546,000 | 5,902,000 |  |  |  |  | 
| Percentage Of Placement Agent Fee |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  | 
| Proceeds from Issuance of Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 57,800,000 |  |  |  |  |  |  | 
| Net Proceeds From Issuance Of Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 51,500,000 |  |  |  |  |  |  | 
| Stock Issued For Exercise Of Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,000 |  |  |  |  |  |  | 
| Warrant Purchase Price Per Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  | 
| Stock Issued During Period Shares warrants Exercised |  |  |  |  |  |  | 2,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Issued During Period, Shares, New Issues |  |  |  |  |  |  | 10,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Issued During Period, Value of Warrants Excercised |  |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Equity Method Investment, Ownership Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.00% | 
| Plan 2013 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Based compensation, shares available for issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,339,720 |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,300,000 |  |  |  |  |  |  | 
| Plan 2007 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |  | 
| Lindsay A Rosenwald [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Price |  |  |  | $ 1.61 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| After Amendment [Member] | Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.001 |  |  |  |  |  |  | 
| Capital Units, Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15,000,000 |  |  |  |  |  |  | 
| After Amendment [Member] | Convertible Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.001 |  |  |  |  |  |  | 
| Capital Units, Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100,000,000 |  |  |  |  |  |  | 
| Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,000,000 |  |  |  |  |  |  | 
| Chief Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Issued During Period, Shares, Issued for Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  | 
| Mr. George Avgerinos [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  | 2,175,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Former Board Of Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Restricted Stock Units |  | $ 133,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Dr. Rosenwald [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Proceeds from issuance of Common stock |  |  |  | $ 3,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  | 2,175,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Mr. Weiss [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  | 2,175,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Senior Vice President [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Issued During Period, Value, Issued for Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,900,000 |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost |  | $ 3,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage |  | 25.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Avenue Therapeutics, Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Research And Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 21,000 |  |  |  |  |  |  | 
| General And Administrative Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 29,000 |  |  |  |  |  |  | 
| Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 50,400 |  |  |  |  |  |  | 
| Weighted Market Value Percentage of Invested Capital |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 44.80% |  |  |  |  |  |  | 
| Weighted Average Cost Percentage of Capital |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  | 
| Shares Issued, Price Per Share |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.146 |  |  |  |  |  |  | 
| Avenue Therapeutics, Inc. [Member] | Consultants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Research And Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 21,000 |  |  |  |  |  |  | 
| Stock Issued During Period, Shares, Issued for Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 150,000 |  |  |  |  |  |  | 
| Avenue Therapeutics, Inc. [Member] | Chief Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Issued During Period, Shares, Issued for Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  | 
| Avenue Therapeutics, Inc. [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  | 
| Avenue Therapeutics, Inc. [Member] | Share-based Compensation Award, Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12.50% |  |  |  |  |  |  | 
| Avenue Therapeutics, Inc. [Member] | Share-based Compensation Award, Tranche Three [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  | 
| Journey Medical Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Price |  |  |  |  |  |  |  |  | $ 0.65 |  |  |  |  |  |  |  |  |  |  |  |  | 
| General And Administrative Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 597,000 |  |  |  |  |  |  | 
| Weighted Market Value Percentage of Invested Capital |  |  |  |  |  |  |  |  | 44.50% |  |  |  |  |  |  |  |  |  |  |  |  | 
| Weighted Average Cost Percentage of Capital |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross |  |  |  |  |  |  |  |  | 1,950,000 |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares, Beginning Balance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,250,000 |  |  |  | 
| Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 800,000 |  |  |  | 
| Checkpoint Therapeutics, Inc [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.065 | $ 4.39 |  |  |  |  |  |  | 
| Research And Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4.39 |  |  |  |  |  |  | 
| Fair Value Assumptions, Weighted Average Volatility Rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  |  |  |  |  |  |  |  |  |  | 48 months |  |  |  |  |  |  |  | 
| Weighted Average Cost Percentage of Capital |  |  |  |  |  |  |  |  |  |  |  |  |  | 44.80% |  |  |  |  |  |  |  | 
| Class of Warrant or Right, Number of Securities Called by Warrants or Rights |  |  |  |  |  |  |  | 0.129 |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Fair Value Assumptions, Risk Free Interest Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 83.00% |  |  |  |  |  |  | 
| Number Of Warrants Granted On Common Stock For Services |  |  |  |  |  |  |  | 100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Marketability Percentage Of Invested Capital |  |  |  |  |  |  |  | 44.10% |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Percentage Of Weighted Average Cost Of Capital |  |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Equity Method Investment, Ownership Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 37.70% |  |  |  |  |  |  | 
| Checkpoint Therapeutics, Inc [Member] | Chief Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate | 83.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate | 1.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Price | $ 4.39 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation | $ 265,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Checkpoint Therapeutics, Inc [Member] | Chief Executive Officer [Member] | Installments One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Achievement Of Fully Diluted Market Capitalizations Value | $ 250,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Achievement Of Fully Diluted Market Capitalizations Common Stock Per Share | $ 4.26 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Checkpoint Therapeutics, Inc [Member] | Chief Executive Officer [Member] | Installments Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Achievement Of Fully Diluted Market Capitalizations Value | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Achievement Of Fully Diluted Market Capitalizations Common Stock Per Share | $ 3.89 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Checkpoint Therapeutics, Inc [Member] | Chief Executive Officer [Member] | Installments Three [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Achievement Of Fully Diluted Market Capitalizations Value | $ 750,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Achievement Of Fully Diluted Market Capitalizations Common Stock Per Share | $ 3.64 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| JMC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 597,000 |  |  |  |  |  |  | 
| Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,800,000 | 1,100,000 | 3,000,000 |  |  |  |  | 
| Research and Development Expense [Member] | Checkpoint Therapeutics, Inc [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation |  |  |  |  |  |  |  | $ 13,000 |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8,500,000 | 4,400,000 | $ 2,900,000 |  |  |  |  | 
| Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 400,000 | 4,343,692 |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.3 |  |  |  |  |  |  | 
| Deferred Compensation Arrangement with Individual, Shares Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 290,000 |  |  |  |  |  |  | 
| Restricted Stock [Member] | Checkpoint Therapeutics, Inc [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Stock-based compensation weighted-average vesting period |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year 8 months 12 days |  |  |  |  |  |  | 
| Share Based Compensation Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,600,000 |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross |  | 40,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000 |  |  |  |  |  |  | 
| Restricted Stock Units (RSUs) [Member] | Senior Vice President [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 300,000 |  |  |  |  |  |  | 
| Restricted Stock Units (RSUs) [Member] | Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross |  | 50,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| New Award [Member] | Senior Vice President [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost |  | $ 3,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Old Award [Member] | Senior Vice President [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost |  | $ 400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Employee Stock Purchase Plan to eligible employees, Reckoning fair value percentage during offering period |  |  |  |  | 85.00% | 85.00% |  |  |  |  | 85.00% |  | 85.00% |  |  |  |  |  | 85.00% | 85.00% |  | 
| Common Stock issued in connection with the first ESPP offering |  |  | 14,681 |  | 7,139 | 13,317 |  |  |  | 6,841 | 6,065 |  | 21,505 |  | 91,192 |  |  |  |  |  |  | 
| Common Stock Par Or Stated Value Per Share |  |  |  |  | $ 1.45 | $ 2.41 |  |  |  |  | $ 1.39 |  | $ 3.88 |  |  |  |  |  | $ 1.80 | $ 1.80 |  | 
| Share Price |  |  |  |  | $ 1.71 | $ 2.84 |  |  |  | $ 2.12 | $ 1.64 |  | $ 4.56 |  |  |  |  |  | $ 2.12 |  |  | 
| Proceeds from Stock Options Exercised |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 200,000 | $ 600,000 |  |  |  |  |  | 
| Common Stock, Capital Shares Reserved for Future Issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 108,808 |  |  |  |  |  |  |