Development, Commercialization and Supply Agreement - Additional Information (Detail)	1 Months Ended						3 Months Ended		12 Months Ended
	Feb. 29, 2020 USD ($)	Jan. 31, 2020 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2016 USD ($)	Feb. 28, 2015 USD ($)	Mar. 31, 2020 USD ($) Item	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
License And Collaboration Agreements [Line Items]
Revenue recognized related to upfront and milestone payments							$ 2,789,000	$ 547,000
Licenses revenue							154,993,000	73,278,000
Deferred revenue							21,807,000	20,163,000	$ 20,846,000	$ 20,710,000
Product Revenue, Net
License And Collaboration Agreements [Line Items]
Licenses revenue							$ 152,204,000	72,731,000
Mochida | In-licenses
License And Collaboration Agreements [Line Items]
Milestones payment		$ 1,000,000.0
Mochida | In-licenses | Research and Development Expense
License And Collaboration Agreements [Line Items]
Upfront payment										$ 2,700,000
Eddingpharm | Out-licenses
License And Collaboration Agreements [Line Items]
Non-refundable up-front received						$ 15,000,000.0
Number of indications of the regulatory milestone events relating to the submission and approval | Item							3
Amounts to be received upon achievement of the regulatory milestone events							$ 33,000,000.0
Sales-based milestone event payment							120,000,000.0
Revenue recognized related to upfront and milestone payments							600,000
Deferred revenue							12,400,000		13,000,000.0
Eddingpharm | Out-licenses | Licensing Revenue
License And Collaboration Agreements [Line Items]
Licenses revenue							3,600,000		3,000,000.0
Eddingpharm | Out-licenses | Maximum
License And Collaboration Agreements [Line Items]
Additional upfront payment eligible to receive based on development, regulatory and sales Milestone							153,000,000.0
Amounts to be received upon achievement of the regulatory milestone events							15,000,000.0
Sales-based milestone event payment							50,000,000.0
Revenue recognized related to upfront and milestone payments								100,000
Eddingpharm | Out-licenses | Minimum
License And Collaboration Agreements [Line Items]
Amounts to be received upon achievement of the regulatory milestone events							2,000,000.0
Sales-based milestone event payment							5,000,000.0
Eddingpharm | Out-licenses | Clinical Trial Application
License And Collaboration Agreements [Line Items]
Non-refundable milestone payment					$ 1,000,000.0
Biologix FZCo | Out-licenses
License And Collaboration Agreements [Line Items]
Revenue recognition period of non-refundable up-front payment					10 years
Biologix FZCo | Out-licenses | Product Revenue, Net
License And Collaboration Agreements [Line Items]
Licenses revenue								300,000
HLS | Out-licenses
License And Collaboration Agreements [Line Items]
Non-refundable up-front received				$ 5,000,000.0
Non-refundable milestone payment	$ 2,500,000	$ 3,800,000	$ 2,500,000	$ 2,500,000
Revenue recognized related to upfront and milestone payments							2,200,000	$ 400,000
Deferred revenue							8,600,000		7,100,000
Non-refundable up-front received period				6 months
Non-refundable milestone payment received				$ 3,800,000
HLS | Out-licenses | Health Canada
License And Collaboration Agreements [Line Items]
Non-refundable milestone payment				2,500,000
HLS | Out-licenses | Licensing Revenue
License And Collaboration Agreements [Line Items]
Licenses revenue							$ 5,100,000		$ 2,900,000
HLS | Out-licenses | Maximum
License And Collaboration Agreements [Line Items]
Additional upfront payment eligible to receive based on development, regulatory and sales Milestone				$ 50,000,000.0