Term Loan Agreement - Additional Information (Detail)				1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Feb. 13, 2019 USD ($)	Jun. 26, 2018 USD ($) $ / shares shares	Mar. 28, 2018 USD ($) Tranche $ / shares shares	Jun. 30, 2018 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2017 USD ($)	Apr. 30, 2019 USD ($)
Term Loan Agreement [Line Items]
Amortization of debt discount (premium)									$ (9,000)
Loss on extinguishment of debt							$ (3,810,000)
Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
Amortization of debt discount (premium)							$ 512,000
Senior Secured Term Loan [Member] | Warrants [Member]
Term Loan Agreement [Line Items]
Exercise price of issued warrants | $ / shares		$ 1.93	$ 1.10
Initial Advance [Member] | Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
Proceeds from issuance of term loan, net of allocation to the debt warrant			$ 14,600,000
Initial Advance [Member] | Senior Secured Term Loan [Member] | Warrants [Member]
Term Loan Agreement [Line Items]
Warrants issued in connection with loan | shares			409,091
Exercise price of issued warrants | $ / shares			$ 1.10
Fair value of warrants issued			$ 284,000
Additional Advance [Member] | Senior Secured Term Loan [Member] | Warrants [Member]
Term Loan Agreement [Line Items]
Warrants issued in connection with loan | shares		77,721
Exercise price of issued warrants | $ / shares		$ 1.93
Warrants, contingent issuance fair value			$ 69,000
Revaluation of additional advance warrants shares reclassified to equity				$ 87,000
Additional Advance [Member] | SWK Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
Upfront loan origination fee percentage		1.50%
Exit fee percentage payable upon repayment of the total secured term loan		6.00%
Total debt discount		$ 652,000
Loan origination fee, exit fee and other loan transaction costs		299,000
Amortization of deferred debt issue cost through the date of the Additional Advance		97,000
Debt issuance costs remaining balance reclassified to debt discount				$ 202,000
CRG Servicing LLC [Member]
Term Loan Agreement [Line Items]
Restriction of the right to capitalize a portion of quarterly interest in the event of a loan default							So long as no default has occurred and is continuing, the Company may elect on each applicable interest payment date to pay 2.5% of the 12.5% per annum interest as Paid In-Kind (“PIK”), whereby such PIK amount would be added to the aggregate principal amount and accrue interest at 12.5% per annum.
Upfront loan origination fee percentage	1.50%
Minimum liquidity amount	$ 5,000,000
Total debt discount	3,200,000
CRG Servicing LLC [Member] | Period One [Member]
Term Loan Agreement [Line Items]
Annual minimum product revenue	15,000,000
Annual minimum product revenue period							on January 1, 2019 and ending on December 31, 2019
CRG Servicing LLC [Member] | Period Two [Member]
Term Loan Agreement [Line Items]
Annual minimum product revenue	45,000,000
Annual minimum product revenue period							January 1, 2020 and ending on December 31, 2020
CRG Servicing LLC [Member] | Period Three [Member]
Term Loan Agreement [Line Items]
Annual minimum product revenue	80,000,000
Annual minimum product revenue period							January 1, 2021 and ending on December 31, 2021
CRG Servicing LLC [Member] | Period Four [Member]
Term Loan Agreement [Line Items]
Annual minimum product revenue	$ 90,000,000
Annual minimum product revenue period							January 1, 2022 and ending on December 31, 2022
CRG Servicing LLC [Member] | Loan Prepayment Prior to December 31, 2019 [Member]
Term Loan Agreement [Line Items]
Principal prepayment premium percentage	10.00%
CRG Servicing LLC [Member] | Loan Prepayment after December 31, 2019 and Prior to December 31, 2020 [Member]
Term Loan Agreement [Line Items]
Principal prepayment premium percentage	5.00%
CRG Servicing LLC [Member] | Loan prepayment after December 31, 2020 and prior to December 31, 2021 [Member]
Term Loan Agreement [Line Items]
Principal prepayment premium percentage	3.00%
CRG Servicing LLC [Member] | Loan prepayment after December 31 2021 [Member]
Term Loan Agreement [Line Items]
Principal prepayment premium percentage	0.00%
CRG Servicing LLC [Member] | Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
Agreement date	Feb. 13, 2019
Senior secured term loan borrowing facility	$ 60,000,000
Term loan agreement, initial advance	$ 35,000,000
Line of Credit Facility, Remaining Borrowing Capacity subject to milestone achievement										$ 10,000,000
Maturity date	Dec. 31, 2023
Annual interest rate on term loan balance	12.50%
Paid in Kind Interest Added to Principal							$ 1,100,000
Exit fee percentage payable upon repayment of the total secured term loan	6.00%
Upfront loan original fee payment, initial advance	$ 525,000
Reimbursement of lender's legal fees and other transaction costs	350,000
Exit fee accrued	2,100,000
Line of credit facility, legal and other transaction costs	591,000
CRG Servicing LLC [Member] | Second Advance [Member]
Term Loan Agreement [Line Items]
Term loan agreement, additional loan advance										$ 15,000,000
Total debt discount	$ 1,100,000
CRG Servicing LLC [Member] | Second Advance [Member] | Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
One-time upfront financing fee percentage applied to borrowing amounts under the line of credit facility	1.50%
Upfront loan original fee payment, initial advance	$ 225,000
Exit fee accrued	$ 900,000
CRG Servicing LLC [Member] | Initial Advance [Member] | Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
One-time upfront financing fee percentage applied to borrowing amounts under the line of credit facility	1.50%
Upfront loan original fee payment, initial advance	$ 525,000
SWK Funding LLC [Member] | Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
Agreement date			Mar. 28, 2018
Senior secured term loan borrowing facility			$ 20,000,000
Term loan agreement, initial advance			$ 15,000,000
Maturity date			Mar. 27, 2023
Exit fee percentage payable upon repayment of the total secured term loan			6.00%
Amortization of debt discount (premium)					$ 84,000
Senior secured term loan, additional advance that followed satisfaction of applicable conditions		$ 5,000,000
Loss on extinguishment of debt					(3,800,000)
Write-off of remaining unamortized debt discount included as a component of the loss on extinguishment of debt					$ 2,300,000
Amortized deferred debt issue costs and debt discount						$ 312,000		$ 209,000
SWK Funding LLC [Member] | Senior Secured Term Loan [Member] | Loan Refinancing [Member]
Term Loan Agreement [Line Items]
Prepayment penalty for voluntary repayment of the secured term loan	1,200,000
Payment of contractual 6% exit fee upon repayment of secured term loan	1,200,000
Payment of accrued and unpaid interest through the date of the secured term loan refinancing	664,000
Payment of additional make-whole interest from the loan refinancing date through the first anniversary of the secured term loan (Mar 28, 2019)	306,000
SWK Funding LLC [Member] | Senior Secured Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member]
Term Loan Agreement [Line Items]
Interest rate							Three-month LIBOR rate (subject to a 1.5% floor) plus 10.50%.
LIBOR rate floor			1.50%
Interest rate percentage above LIBOR rate			10.50%
Repayment of senior secured term loan	$ 20,000,000
First Tranche Advance [Member] | SWK Senior Secured Term Loan [Member]
Term Loan Agreement [Line Items]
Upfront loan origination fee percentage			1.50%
Total debt discount			$ 2,100,000
Cost allocated tranches, number | Tranche			2
Loan origination fee, exit fee and other loan transaction costs			$ 1,800,000
Aggregate fair value of warrants			$ 353,000