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Commitments and Contingencies - Manufacturing, License and Other Agreements (Details) - USD ($) $ in Thousands	Dec. 30, 2016	Dec. 31, 2018	Dec. 31, 2017
TRX518 and DKN-01
Commitments and Contingencies
Noncancelable commitments			$ 154
License and service agreements
Commitments and Contingencies
Paid or accrued royalties		$ 0
License and service agreements \| Preferred Class A
Commitments and Contingencies
Issuance of stock in consideration for license (in shares)	9,000,000
Licensing agreements
Commitments and Contingencies
Paid or accrued royalties		$ 0