Revenue - Additional Information (Detail) - USD ($)		3 Months Ended
	Dec. 31, 2020	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Disaggregation Of Revenue [Line Items]
Revenue		$ 7,683,000	$ 9,294,000
Ocumension Therapeutics [Member] | Share Offering [Member]
Disaggregation Of Revenue [Line Items]
Issuance of stock, net of issue costs, shares	3,010,722
RPA [Member] | SWK [Member]
Disaggregation Of Revenue [Line Items]
Upfront cash payment		16,500,000
Revenue		255,000	225,000
Royalty payments		727,000	724,000
Deferred revenue, current		1,200,000		$ 1,200,000
Deferred revenue, non-current		13,300,000		$ 13,600,000
Product [Member]
Disaggregation Of Revenue [Line Items]
Revenue		7,394,000	9,010,000
Product [Member] | Ocumension Therapeutics [Member]
Disaggregation Of Revenue [Line Items]
Revenue		11,000	56,000
License and Collaboration Agreement [Member]
Disaggregation Of Revenue [Line Items]
Revenue		34,000	59,000
License and Collaboration Agreement [Member] | Ocumension Therapeutics [Member]
Disaggregation Of Revenue [Line Items]
Revenue		30,000	59,000
Royalty Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue		255,000	225,000
Royalty Income [Member] | Ocumension Therapeutics [Member]
Disaggregation Of Revenue [Line Items]
Revenue		0	0
Product Sales, License and Collaboration Revenue, or Royalty Income [Member] | Exclusive License Agreement with Betta Pharmaceuticals, Co., Ltd.
Disaggregation Of Revenue [Line Items]
Revenue		0	0
Collaborative Research and Development [Member]
Disaggregation Of Revenue [Line Items]
Revenue		$ 0	$ 0