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Significant Accounting Policies (Details Textual) - USD ($) |  |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2019 | Mar. 13, 2018 | Mar. 12, 2018 | Mar. 13, 2017 | Jan. 31, 2019 | Aug. 31, 2017 | Jul. 31, 2016 | Dec. 31, 2018 | Dec. 31, 2017
Property Plant And Equipment Design Costs Capitalized |  |  |  |  |  |  |  | $ 400,000 |
Certificates of Deposit, at Carrying Value |  |  |  |  |  |  |  | $ 27,600,000 | $ 40,000,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  |  |  |  |  |  | 21.00% | 35.00%
Preferred Stock, Dividend Rate, Percentage |  |  |  |  | 2.00% |  |  |  |
Subsequent Event [Member] | Accounting Standards Update 2016-02 [Member] |  |  |  |  |  |  |  |  |
Additional Operating Lease Liability | $ 1.9 |  |  |  |  |  |  |  |
Scenario, Plan [Member] |  |  |  |  |  |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  |  |  |  |  |  |  | 21.00%
Held-to-maturity Securities [Member] |  |  |  |  |  |  |  |  |
Time Deposits, at Carrying Value |  |  |  |  |  |  |  | $ 17,600,000 | $ 26,000,000
Cash and Cash Equivalents [Member] |  |  |  |  |  |  |  |  |
Time Deposits, at Carrying Value |  |  |  |  |  |  |  | $ 10,000,000 | 14,000,000
Fortress Biotech, Inc [Member] |  |  |  |  |  |  |  |  |
Research and Development Asset Acquired Other than Through Business Combination, Fair Value Acquired |  |  |  |  |  |  |  |  | $ 9,600,000
Stock Issued During Period, Shares, Issued for Services | 709,314 |  |  | 767,264 |  |  |  |  |
Preferred Stock, Dividend Rate, Percentage | 2.00% | 2.50% | 2.50% |  |  | 2.50% |  |  |
Fortress Biotech, Inc [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services | 709,314 |  |  |  |  |  |  |  |
Series A Preferred Stock [Member] |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services |  |  |  |  |  |  | 250,000 |  |
Series A Preferred Stock [Member] | Fortress Biotech, Inc [Member] |  |  |  |  |  |  |  |  |
Preferred Stock, Dividend Rate, Percentage |  |  |  |  |  |  | 2.50% |  |

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- Definition A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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