Segment Reporting (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Product revenues	$ 259,540	$ 240,056	$ 624,214	$ 741,303
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
United States
Segment Reporting Information [Line Items]
Product revenues	$ 111,189	$ 111,570	$ 264,204	$ 340,656
Germany
Segment Reporting Information [Line Items]
Product revenues	14,553	20,379	41,144	63,889
South Korea
Segment Reporting Information [Line Items]
Product revenues	23,260	14,543	60,062	45,098
Japan
Segment Reporting Information [Line Items]
Product revenues	15,280	20,508	40,766	59,102
China
Segment Reporting Information [Line Items]
Product revenues	27,363	17,591	63,883	49,598
Czech Republic
Segment Reporting Information [Line Items]
Product revenues	9,414	8,805	25,007	30,956
Canada
Segment Reporting Information [Line Items]
Product revenues	8,079	8,833	19,430	29,226
Romania
Segment Reporting Information [Line Items]
Product revenues	9,957	6,556	20,576	19,487
United Kingdom
Segment Reporting Information [Line Items]
Product revenues	5,737	8,315	14,106	23,980
Other
Segment Reporting Information [Line Items]
Product revenues	34,708	22,956	75,036	79,311
Non U.S.
Segment Reporting Information [Line Items]
Product revenues	$ 148,351	$ 128,486	$ 360,010	$ 400,647