Debt and capital lease obligations - Term Loan Agreements (Details) - USD ($)	1 Months Ended		3 Months Ended
	Oct. 31, 2020	Sep. 30, 2019	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Final payment fee to be paid upon termination			$ 1,625,000
Amortization of final payment fee			$ 81,000
Period of straight-line amortization			24 months
Effective interest rate at end of period			7.85%
Final payment fee to be paid upon termination (as a percent)			5.00%
Prepayment fee percent , year one			3.00%
Prepayment fee percent, year two			2.00%
Prepayment fee percent, year three			1.00%
Short-term debt obligation			$ 1,238,000			$ 1,032,000
Long-term debt obligation			$ 33,388,000			$ 33,488,000
LIBOR
Debt Instrument [Line Items]
LIBOR floor			1.50%
Innovatus Term Loan
Debt Instrument [Line Items]
Principal amount		$ 25,000,000
Cash interest, effective interest rate for first 24 months		24.00%
Period for deferred interest		$ 7.25
Deferred interest, effective interest rate for first 24 months		1.75%
Monthly principal payment		$ 1,079,000
Frequency of principal payment		1,079 Per Month
Final payment fee to be paid upon termination		$ 750,000
Amortization of final payment fee			$ 0	$ 31,000
Repayments of debt	$ 26,882,000
Innovatus Term Loan | Prime
Debt Instrument [Line Items]
Interest rate a)		5.25%
Interest rate b) variable rate spread		3.75%
Midcap Trust Term Loan
Debt Instrument [Line Items]
Credit facility amount	37,500,000
Proceeds received	$ 32,500,000
Amount available to be drawn during Q2					$ 5,000,000
PPP loan
Debt Instrument [Line Items]
Short-term debt obligation			1,200,000
Long-term debt obligation			$ 1,300,000