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Share Capital (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended								12 Months Ended
	Jan. 01, 2020	Jan. 31, 2020	Dec. 31, 2019	Nov. 30, 2019	Sep. 30, 2018	Jul. 31, 2018	May 31, 2018	Mar. 31, 2018	Jun. 30, 2014	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Share Capital [Line Items]
Sale proceeds of common shares										$ 27,396	$ 102,850
Number of Options Exercisable			1,946,026							1,946,026
Options Exercisable Weighted Average Remaining Contractual Life in Years										5 years 4 months 24 days
Aggregate fair value of options vested										$ 3,255	$ 2,861
Unrecognized stock-based compensation cost			$ 8,460							$ 8,460
Unrecognized stock-based compensation expected to be recognized over a period										2 years 6 months 18 days
Series1 Preferred Shares
Share Capital [Line Items]
Conversion of shares											1,852,000
Common Shares [Member]
Share Capital [Line Items]
Conversion of shares											1,852,000
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]
Shares issued								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]
Shares issued								2,868,000
Two Thousand Fourteen Plan [Member]
Share Capital [Line Items]
Number of Options, Granted			99,818							99,818
Inducement Plan [Member]
Share Capital [Line Items]
Number of Options, Granted			264,750							264,750
Common shares reserved for issuance												400,000
Subsequent Event [Member] \| Two Thousand Fourteen Plan [Member]
Share Capital [Line Items]
Common stock reserved for issuance	1,028,806
Maximum [Member] \| Amended And Restated Stock Option Plan [Member]
Share Capital [Line Items]
Options exercise term										10 years
Options vesting period										4 years
Maximum [Member] \| Two Thousand Fourteen Plan [Member]
Share Capital [Line Items]
Options exercise term									10 years
Options vesting period									4 years
Common Shares [Member]
Share Capital [Line Items]
Shares issued										2,214,490	9,540,000
Conversion of shares											1,852,000
Common Shares [Member] \| Neurocrine Collaboration Agreement [Member]
Share Capital [Line Items]
Sale proceeds of common shares			$ 20,000
Shares issued			1,408,847
Aggregate purchase price per share			$ 14.196							$ 14.196
Common stock purchase price premium at fair value			$ 3,333
Lock-up restrictions and standstill agreement period			2 years
Stifel [Member] \| At-The-Market Equity Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares							$ 29,200
Stifel [Member] \| At-The-Market Equity Offering [Member] \| Maximum [Member]
Share Capital [Line Items]
Sale proceeds of common shares							$ 30,000
Stifel [Member] \| At-The-Market Equity Offering [Member] \| Common Shares [Member]
Share Capital [Line Items]
Shares issued							3,440,000
Jefferies and Stifel [Member] \| At-The-Market Equity Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares										$ 10,771
Jefferies and Stifel [Member] \| At-The-Market Equity Offering [Member] \| Subsequent Event [Member]
Share Capital [Line Items]
Sale proceeds of common shares		$ 37,979
Jefferies and Stifel [Member] \| At-The-Market Equity Offering [Member] \| Maximum [Member]
Share Capital [Line Items]
Sale proceeds of common shares				$ 50,000
Jefferies and Stifel [Member] \| At-The-Market Equity Offering [Member] \| Common Shares [Member]
Share Capital [Line Items]
Shares issued										805,643
Jefferies and Stifel [Member] \| At-The-Market Equity Offering [Member] \| Common Shares [Member] \| Subsequent Event [Member]
Share Capital [Line Items]
Shares issued		2,446,687
Jefferies and Stifel [Member] \| At-The-Market Equity Offering Sales Agreement [Member]
Share Capital [Line Items]
Sale proceeds of common shares						$ 14,820
Jefferies and Stifel [Member] \| At-The-Market Equity Offering Sales Agreement [Member] \| Maximum [Member]
Share Capital [Line Items]
Sale proceeds of common shares						$ 50,000
Jefferies and Stifel [Member] \| At-The-Market Equity Offering Sales Agreement [Member] \| Common Shares [Member]
Share Capital [Line Items]
Shares issued						1,600,000
Jefferies and Stifel [Member] \| Underwritten Public Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares					$ 59,220
Jefferies and Stifel [Member] \| Underwritten Public Offering [Member] \| Common Shares [Member]
Share Capital [Line Items]
Shares issued					4,500,000
Shares price					$ 14.00