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v3.19.2

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Apr. 30, 2019 | Apr. 19, 2019 | May 31, 2019 | Apr. 30, 2019 | Mar. 29, 2019 | Aug. 31, 2018 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  | 39,454,316 |  | 39,454,316 |  | 26,610,183
Proceeds from Issuance of Common Stock |  |  |  |  |  |  |  |  |  | $ 31,625 |  |
Shelf Registration Statement Remaining Unissued Capital |  |  |  |  |  |  |  | $ 20,900 |  | 20,900 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  | 5,000,000 |  | 5,000,000 |  | 5,000,000 |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  |  |  |  | 3,000,000 |  |  |  |  |
General and Administrative Expense. |  |  |  |  |  |  |  | $ 3,189 | $ 1,683 | 5,533 | $ 3,793 |
Annual Fees Expenses On Founders Agreement |  |  |  |  |  |  |  |  |  | 400 |  |
Proceeds From Horizon Notes |  |  |  |  |  |  |  |  |  | $ 15,000 | $ 0 |
City of Hope |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Conversion of Stock, Shares Issued |  |  |  | 137,608 |  |  |  |  |  |  |  |
Market Offering |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  | 3,500,000 |  | 3,500,000 |  | 0
Share price |  |  |  |  |  |  |  | $ 6.42 |  | $ 6.42 |  |
Shelf Registration Statement, Aggregate Fee Paid |  |  |  |  |  |  |  |  |  | $ 500 |  |
Proceeds from Issuance of Common Stock |  |  |  |  |  |  |  |  |  | 22,000 |  |
Proceeds From Horizon Notes |  |  |  |  |  |  |  | $ 22,500 |  | $ 22,500 |  |
Market Offering | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Shelf Registration Statement, Maximum Authorized Common Stock Issuance, Value |  |  |  |  |  | $ 75,000 |  |  |  |  |  |
Agent commission (as a percent) |  |  |  |  |  | 3.00% |  |  |  |  |  |
Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued | 6,875,000 |  |  | 6,875,000 |  |  |  |  |  |  |  |
Share price | $ 4.00 |  |  | $ 4.00 |  |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock | $ 29,500 |  |  |  |  |  |  |  |  |  |  |
Proceeds From Horizon Notes |  |  |  | $ 31,600 |  |  |  |  |  |  |  |
Aggregate Fees, Public Offering | $ 2,100 |  |  |  |  |  |  |  |  |  |  |
Public Offering [Member] | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Option to purchase additional shares |  |  |  | 1,031,250 |  |  |  |  |  |  |  |
Incentive Plan 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period |  |  |  |  |  |  |  |  |  | 10 years |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  |  | 1,987,439 |  | 1,987,439 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  |  |  |  |  |  |  | 2,000,000 |  |
Employee Stock Option |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  | $ 800 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  |  |  |  |  |  | 1 year 7 months 6 days |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number |  |  |  |  |  |  |  | 310,419 |  | 310,419 |  |
Employee Stock Option | Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  | $ 1,600 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  |  |  |  |  |  | 2 years 2 months 12 days |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number |  |  |  |  |  |  |  | 68,160 |  | 68,160 |  |
Employee Stock Option | Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  | $ 2,900 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  |  |  |  |  |  | 1 year 10 months 24 days |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services |  |  |  |  |  |  |  |  |  | 709,314 | 834,756 |
Conversion of Stock, Shares Converted |  |  |  | 137,608 |  |  |  | 137,608 |  | 137,608 |  |
Class A Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  | 862,392 |  | 862,392 |  | 1,000,000
Stock Issued During Period, Shares, Issued for Services |  |  |  |  |  |  |  |  |  | 0 | 0 |
Conversion of Stock, Shares Converted |  |  |  | 137,608 |  |  |  | (137,608) |  | (137,608) |  |
Class A Common Shares | City of Hope |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Conversion of Stock, Shares Converted |  |  |  | 137,608 |  |  |  |  |  |  |  |
Fortress Biotech, Inc |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services |  |  |  |  | 108,069 |  |  |  |  |  |  |
Shares Of Common Stock, Percentage |  |  |  |  | 2.50% |  |  |  |  |  |  |
Proceeds From Horizon Notes |  | $ 22,500 |  |  |  |  |  |  |  |  |  |
Fortress Biotech, Inc | Market Offering |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services |  |  |  | 87,656 |  |  |  |  |  |  |  |
Shares Of Common Stock, Percentage | 2.50% |  |  | 2.50% |  |  |  |  |  |  |  |
General and Administrative Expense. |  |  |  |  |  |  |  |  |  | $ 500 |  |
Proceeds From Horizon Notes |  |  |  | $ 22,500 |  |  |  |  |  |  |  |
Fortress Biotech, Inc | Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  | 197,656 |  |  |  |  |  |  |  |  |
Shares Of Common Stock, Percentage |  |  | 2.50% |  |  |  |  |  |  |  |  |
General and Administrative Expense. |  |  | $ 800 |  |  |  |  |  |  |  |  |
Proceeds From Horizon Notes |  |  | $ 31,600 |  |  |  |  |  |  |  |  |

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