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Term Loan (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	May 31, 2020	Jun. 30, 2020	Jun. 30, 2020	Aug. 31, 2018
Debt Instrument [Line Items]
Loss on repayment of term loan (note 9)		$ (988)	$ (988)
Silicon Valley Bank [Member] \| Term Loan [Member] \| Loan Agreement [Member]
Debt Instrument [Line Items]
Aggregate principal amount of debt instrument				$ 15,500
Debt instrument, final payment fee	$ 1,008
Debt instrument prepayment fee	$ 225
Warrants outstanding to purchase common stock		40,000	40,000
Warrants exercise price per common share		$ 9.79	$ 9.79
Warrants outstanding to purchase common stock expiration period			2028-08
Loss on repayment of term loan (note 9)			$ 988