REVENUE, CREDIT CONCENTRATIONS AND GEOGRAPHIC INFORMATION - Disaggregates of Total Net Product Revenues from External Customers by Product (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Revenue	$ 1,846,275	$ 1,860,455	$ 1,704,048
Product
Revenue from External Customer [Line Items]
Revenue	1,783,498	1,805,861	1,661,043
Vimizim | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	623,145	544,257	544,345
Kuvan | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	285,776	457,736	463,353
Naglazyme | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	380,449	391,298	374,334
Palynziq | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	237,474	170,983	86,857
Brineura | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	128,034	110,192	71,997
Voxzogo | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	5,855	0	0
Firdapse | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	0	1,288	22,348
Vimizim, Kuvan, Naglazyme, Palynziq, Brineura, and Firdapse | Marketed by Company
Revenue from External Customer [Line Items]
Revenue	1,660,733	1,675,754	1,563,234
Aldurazyme | Marketed by Sanofi
Revenue from External Customer [Line Items]
Revenue	122,765	130,107	97,809
Royalty and Other Revenues
Revenue from External Customer [Line Items]
Revenue	$ 62,777	$ 54,594	$ 43,005