Segment Reporting (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Product revenues	$ 206,182	$ 160,520	$ 400,120	$ 308,610
Total product revenues in percentage	100.00%	100.00%	100.00%	100.00%
United States
Segment Reporting Information [Line Items]
Product revenues	88,850	71,569	173,917	134,627
Total product revenues in percentage	43.00%	45.00%	43.00%	44.00%
Germany
Segment Reporting Information [Line Items]
Product revenues	25,486	20,492	47,962	40,365
Total product revenues in percentage	12.00%	13.00%	12.00%	13.00%
South Korea
Segment Reporting Information [Line Items]
Product revenues	24,039	14,028	45,954	25,487
Total product revenues in percentage	12.00%	9.00%	11.00%	8.00%
China
Segment Reporting Information [Line Items]
Product revenues	17,349	15,548	33,293	29,600
Total product revenues in percentage	8.00%	10.00%	8.00%	10.00%
Japan
Segment Reporting Information [Line Items]
Product revenues	11,856	9,299	22,321	18,272
Total product revenues in percentage	6.00%	6.00%	6.00%	6.00%
Czech Republic
Segment Reporting Information [Line Items]
Product revenues	6,855	4,118	12,941	7,756
Total product revenues in percentage	3.00%	2.00%	3.00%	2.00%
United Kingdom
Segment Reporting Information [Line Items]
Product revenues	6,199	4,007	12,799	8,131
Total product revenues in percentage	3.00%	3.00%	3.00%	3.00%
Mexico
Segment Reporting Information [Line Items]
Product revenues	5,058	4,023	9,761	7,450
Total product revenues in percentage	2.00%	2.00%	2.00%	2.00%
Canada
Segment Reporting Information [Line Items]
Product revenues	4,569	3,582	7,731	7,085
Total product revenues in percentage	2.00%	2.00%	2.00%	2.00%
Other
Segment Reporting Information [Line Items]
Product revenues	15,921	13,854	33,441	29,837
Total product revenues in percentage	8.00%	8.00%	10.00%	10.00%
Total Foreign
Segment Reporting Information [Line Items]
Product revenues	$ 117,332	$ 88,951	$ 226,203	$ 173,983
Total product revenues in percentage	57.00%	55.00%	57.00%	56.00%