Commitments and Contingencies - Additional Information (Detail)	1 Months Ended			3 Months Ended			6 Months Ended		12 Months Ended
	Aug. 31, 2019 $ / shares shares	Nov. 30, 2017 USD ($)	May 31, 2017 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($) Vehicle	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) Vehicle	Jan. 01, 2019 USD ($)	Jul. 01, 2013 USD ($)
Commitments And Contingencies [Line Items]
Purchase obligation extended term	2026
Supply Agreement expiration period							Dec. 31, 2026
Supply Agreement renewal period							2 years
Operating lease, non-current liabilities				$ 1,843,000			$ 1,843,000		$ 2,514,000
Operating lease costs				400,000	$ 300,000		700,000	$ 800,000
Operating lease, cash paid				400,000	200,000		900,000	700,000
Variable lease costs				100,000	$ 100,000		200,000	$ 200,000
Lease Agreement with Enterprise | Vehicle Leases
Commitments And Contingencies [Line Items]
Number of vehicle leases | Vehicle						119			90
Operating lease rent expenses						$ 83,000			$ 65,000
Number of vehicle leases removed | Vehicle									29
Lease expiration period						48 months
Operating lease right-of-use assets										$ 1,600,000
Operating lease liabilities										1,900,000
Operating lease, non-current other assets										1,600,000
Operating lease, other current liabilities										600,000
Operating lease, non-current liabilities										1,300,000
MidCap Credit Facility
Commitments And Contingencies [Line Items]
Warrants to purchase common stock | shares	1,171,614
Exercise price of warrants | $ / shares	$ 1.11
Deerfield | Milestone Rights Liability
Commitments And Contingencies [Line Items]
Contingent liability remain payable				$ 70,000,000.0			$ 70,000,000.0
Deerfield | Milestone Rights Liability | Maximum
Commitments And Contingencies [Line Items]
Contingent liability for milestone payments											$ 90,000,000.0
Russell Ranch Road II LLC | Office Lease
Commitments And Contingencies [Line Items]
Operating lease rent expenses		$ 35,969	$ 40,951
Operating lease right-of-use assets										3,200,000
Operating lease liabilities										3,500,000
Operating lease, other current liabilities										900,000
Operating lease, non-current liabilities										$ 2,600,000
Percentage of annual increase in lease payment		3.00%	3.00%
Lease expiration		2023-01	2023-01
Lease renewal option		5 years	5 years
Reimbursement amount received for tenant improvements		$ 56,325