Number of shares issued for each share of convertible preferred stock that is converted.

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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Describe the conversion features of preferred stock if preferred stock is convertible. That is, shares of preferred stock into which another convertible security was converted, or shares of preferred stock into which another class of preferred stock was converted.

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Number of new stock issued during the period.

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Collaborative development and license agreement termination date.

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Estimated weighted average cancellation price per share of common stock.

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Maximum beneficial ownership limitation percentage for conversion of common stock issued and outstanding.

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Maximum beneficial ownership limitation upon notice, percentage for conversion of common stock issued and outstanding.

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Maximum beneficial percentage hold for conversion of number Of common stock issued and outstanding.

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Minimum beneficial percentage hold for conversion of number of common stock issued and outstanding.

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Number of common shares agreed to transfer and assign for cancellation.

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Share capital.

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Share Capital (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Mar. 23, 2018	Mar. 07, 2018	Mar. 31, 2018
Share Capital [Line Items]
Gain on termination of collaboration agreement		$ 4,398	$ 4,398
Teva Pharmaceuticals International GmbH and Teva Canada Limited [Member]
Share Capital [Line Items]
Collaborative development and license agreement termination date		Mar. 07, 2018
Teva Canada Limited [Member]
Share Capital [Line Items]
Number of common shares agreed to transfer and assign for cancellation		1,000,000
BVF Partners L.P [Member] \| Exchange Agreement [Member]
Share Capital [Line Items]
Estimated weighted average cancellation price per share of common stock	$ 7.61
BVF Partners L.P [Member] \| Exchange Agreement [Member] \| Series1 Preferred Shares
Share Capital [Line Items]
Issued (cancelled) pursuant to exchange agreement	2,868,000
Preferred shares convertible into common shares	one-for-one
Common shares issued on conversion of preferred stock	1
Maximum beneficial ownership limitation percentage for conversion of common stock issued and outstanding	9.99%
Maximum beneficial ownership limitation upon notice, percentage for conversion of common stock issued and outstanding	19.99%
Maximum beneficial percentage hold for conversion of number Of common stock issued and outstanding	5.00%
Minimum beneficial percentage hold for conversion of number Of common stock issued and outstanding.	5.00%
BVF Partners L.P [Member] \| Exchange Agreement [Member] \| Common Shares [Member]
Share Capital [Line Items]
Issued (cancelled) pursuant to exchange agreement	2,868,000