Share Capital - Schedule of Share Capital (Detail) - shares	Mar. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Registered share capital	80,321,227	75,133,951
Authorized share capital	115,172,786	115,172,786
Employee Benefit Plans [Member]
Class of Stock [Line Items]
Conditional share capital - Bonds or similar debt instruments	15,806,433	17,493,709
Bonds or Similar Debt Instruments [Member]
Class of Stock [Line Items]
Conditional share capital - Bonds or similar debt instruments	4,919,700	4,919,700
Swiss Law [Member]
Class of Stock [Line Items]
Authorized share capital	14,125,426	17,625,426