Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 245,862	$ 237,840	$ 717,837	$ 691,106
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	91,301	93,374	265,945	262,215
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	31,496	24,981	90,601	77,519
Germany
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	25,399	23,484	73,428	69,076
South Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	13,381	12,758	41,629	39,909
France
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	12,054	11,626	36,106	35,782
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	3,179	3,254	9,855	9,882
Other European
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	33,991	36,341	103,765	106,899
Other international
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 35,061	$ 32,022	$ 96,508	$ 89,824