Product Revenue Reserves and Allowances - Additional Information (Detail) - USD ($)				1 Months Ended					12 Months Ended
	Dec. 31, 2020	Dec. 17, 2020	Mar. 31, 2013	Aug. 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Aug. 31, 2019	Nov. 30, 2018	Dec. 31, 2022	Dec. 31, 2021
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									$ 41,404,000	$ 36,939,000
Amended Alimera Science Inc Agreement [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									43,000	54,000
OncoSil Medical UK Limited [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									0
Deferred revenue									$ 100,000	100,000
Receipt of upfront license fee			$ 100,000
Royalty percentage earned from sales of product									8.00%
Percentage of non-royalty consideration received from sublicense									20.00%
License agreement commencement date									2012-12
Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Deferred revenue									$ 0	0
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		$ 6,000,000.0			7,250,000
Potential future payments based on achievement of commercial-based milestones				6,000,000.0		$ 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				11,750,000
Potential future payments based on achievement of remaining development and regulatory milestones				6,250,000
Potential future payments based on achievement of remaining commercial-based milestones				3,000,000.0
Ocumension Therapeutics [Member] | Share Offering [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Issuance of stock, net of issue 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									1,137,000	871,000
Royalty Income [Member] | Amended Alimera Science Inc Agreement [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									0	0
Royalty Income [Member] | Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									269,000	0
RPA [Member] | SWK [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									868,000	872,000
Upfront cash payment		$ 16,500,000
Deferred revenue, current									1,200,000	1,100,000
Deferred revenue, non-current									13,600,000	14,600,000
Royalty payments									2,700,000	2,800,000
Royalty Sale Agreement [Member] | SWK [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Deferred revenue		$ 16,500,000
Collaborative Research and Development [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									0	60,000
Deferred revenue									0	0
Collaborative Research and Development [Member] | OncoSil Medical UK Limited [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									100,000
License and Collaboration Agreement [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									362,000	756,000
License and Collaboration Agreement [Member] | Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									191,000	543,000
Product [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									39,905,000	35,312,000
Product [Member] | Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									363,000	308,000
Technical Assistance [Member] | Ocumension Therapeutics [Member]
Disclosure of Product Revenue Reserves and Allowances [Line Items]
Revenue									$ 188,000	$ 499,000