Revenue - Additional Information (Detail) - USD ($)			1 Months Ended						3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 17, 2020	Aug. 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Aug. 31, 2019	Mar. 31, 2019	Nov. 30, 2018	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									$ 9,059,000	$ 15,695,000	$ 25,395,000	$ 27,306,000
Icon Bioscience Inc [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Accrued sales-based royalty expense									0	908,000	$ 0	1,300,000
Percentage of accelerated milestone payment received											20.00%
Amended Alimera Science Inc Agreement [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									39,000	437,000	$ 53,000	1,600,000
Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Receipt of upfront license fee			$ 9,500,000	$ 2,000,000.0				$ 1,750,000
Potential future payments based on achievement of development and regulatory milestones					$ 6,000,000.0			7,250,000
Potential future payments based on achievement of commercial-based milestones					$ 6,000,000.0			$ 3,000,000.0
Development milestone payment received						$ 1,000,000.0
Potential future payments based on achievement of combined remaining development and sales milestone extinguished			11,750,000
Potential future payments extinguished upon achievement of prescribed remaining development and regulatory milestone			6,250,000
Potential future payments extinguished upon achievement of prescribed remaining commercial sales based milestones			3,000,000.0
Potential future payments extinguished upon achievement of prescribed development and regulatory milestones			6,000,000.0
Potential future payments extinguished upon achievement of prescribed commercial sales based milestone			6,000,000.0
Ocumension Therapeutics [Member] | Share Offering [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Issuance of stock, net of issuance costs, shares	3,010,722
Ocumension Therapeutics [Member] | Maximum [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Product supply milestones and development milestones							$ 7,250,000
Upon achievement of milestones			$ 21,250,000
Royalty Income [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									313,000	402,000	674,000	1,565,000
Royalty Income [Member] | Amended Alimera Science Inc Agreement [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									0	402,000	0	1,600,000
RPA [Member] | SWK [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									313,000	0	674,000	0
Upfront cash payment		$ 16,500,000
Deferred revenue		$ 16,500,000
Royalty payments									1,000,000.0		2,200,000
Royalty Sale Agreement | SWK [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Deferred revenue, current	$ 885,000								1,000,000.0		1,000,000.0
Deferred revenue, non-current	15,600,000								14,800,000		14,800,000
Technical Assistance [Member] | Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									78,000	0	438,000	0
License and Collaboration Agreement [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									159,000	9,535,000	594,000	11,590,000
License and Collaboration Agreement [Member] | Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									0	9,500,000	0	11,500,000
Product [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									8,587,000	5,758,000	24,127,000	14,151,000
Collaborative Research and Development [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									0	$ 0	60,000	$ 15,000
Deferred revenue	$ 60,000								$ 0		$ 0