Share Capital (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended					3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Feb. 29, 2020	Jan. 31, 2020	Nov. 30, 2019	Mar. 31, 2018	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Capital [Line Items]
Sale proceeds of common shares							$ 102,456
Two Thousand Fourteen Plan [Member]
Share Capital [Line Items]
Common stock reserved for issuance	4,000,000
Number of restricted share awards, restricted share unit awards or performance awards available for issue	1,000,000						1,000,000
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
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 cancelled					2,868,000
Common Shares [Member]
Share Capital [Line Items]
Shares issued						6,759,187
Jefferies and Stifel [Member] | At-The-Market Equity Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares			$ 37,979					$ 10,771
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			2,446,687					805,643
Jefferies, Stifel and Guggenheim Securities, LLC [Member] | Underwritten Public Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares			$ 56,700
Additional proceeds from issuance of common stock			$ 8,460
Jefferies, Stifel and Guggenheim Securities, LLC [Member] | Underwritten Public Offering [Member] | Common Shares [Member]
Share Capital [Line Items]
Shares issued		562,500	3,750,000
Shares price			$ 16.00