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Significant Accounting Policies - Additional Information (Details)		3 Months Ended	12 Months Ended
	Aug. 08, 2018 USD ($)	Dec. 31, 2018 USD ($) shares	Dec. 31, 2018 USD ($) Segment shares	Jan. 01, 2019 USD ($)	Dec. 31, 2018 CAD ($) shares	Sep. 30, 2018 shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 shares
Schedule Of Significant Accounting Policies [Line Items]
Revenue from license fee			$ 478,000
Type of Revenue [Extensible List]			us-gaap:LicenseMember
Refund from research and developement tax credit		$ 100,000	$ 100,000
Inventory markdowns to net realizable value			$ 0
Number of stock options outstanding | shares		3,308,049	3,308,049		3,308,049		2,448,646	1,969,000
Modified employee stock options outstanding fair value	$ 10,300,000
Reclassification of stock based compensation liability classified stock options		$ 0	$ 0
Current receivables		200,000	200,000
Non-current receivables		294,000	294,000
Contract assets		0	0
Contract liabilities		0	$ 0
Number of operating segment | Segment			1
Number of reportable segment | Segment			1
Derivative financial instruments		13,769,000	$ 13,769,000				$ 9,578,000
Accounting Standards Update 2016-02 | Subsequent Event
Schedule Of Significant Accounting Policies [Line Items]
Lease liability and right of use asset recognized				$ 700,000
Employee and Non-employee Stock Options
Schedule Of Significant Accounting Policies [Line Items]
Number of stock options outstanding | shares						2,741,146
Non-employee Stock Options
Schedule Of Significant Accounting Policies [Line Items]
Derivative financial instruments		0	$ 0
Minimum
Schedule Of Significant Accounting Policies [Line Items]
Effective income tax rate			50.00%
Leasehold Improvements
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life			5 years
Furniture and Fixtures
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life			7 years
Computer Software and Hardware | Minimum
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life			3 years
Computer Software and Hardware | Maximum
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life			5 years
Equipment
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life			15 years
Strategic Alliance Agreement | Heuro Canada Inc. | HealthTech Connex, Inc.
Schedule Of Significant Accounting Policies [Line Items]
Revenue from license fee		$ 500,000
Type of Revenue [Extensible List]		us-gaap:LicenseMember
Consideration for license					$ 750,000
License consideration first annual installment					250,000
License consideration second annual installment					250,000
License consideration third annual installment					$ 250,000
License Fees | Strategic Alliance Agreement
Schedule Of Significant Accounting Policies [Line Items]
Revenue from license fee			$ 500,000

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