Number of directors to whom the Company agreed to issue warrants to purchase common shares.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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Fair Value of Financial Assets and Liabilities (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017 USD ($) director	Dec. 31, 2016 USD ($)	Oct. 31, 2017 USD ($)
Fair value of Financial Assets and Liabilities
Transfer between levels 1 to level 2	$ 0	$ 0
Transfer between levels 2 to level 1	0	0
Transfer in and out of level 3	$ 0	0
Number of directors to whom the Company agreed to issue warrants \| director	2
Expected dividend yield	0.00%
Fair value of derivative liability	$ 0	512	$ 0
Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities	6,289	20,230
Level 3 \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities	6,289	20,230
Collaborative arrangement \| Yale Agreement
Fair value of Financial Assets and Liabilities
Fair value of derivative liability			$ 0
Warrants to purchase common shares \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities	6,289	780
Warrants to purchase common shares \| Level 3 \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities	$ 6,289	780
Derivative liability \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities		512
Derivative liability \| Level 3 \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities		512
Contingent equity liability \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities		18,938
Contingent equity liability \| Level 3 \| Recurring
Fair value of Financial Assets and Liabilities
Fair value of liabilities		$ 18,938