Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0001013462 (http://www.sec.gov/CIK)

Segments, Geographical Areas [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Segments, Geographical Areas [Abstract]
Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area	Revenue by geographic area is as follows:   Year Ended December 31, (in thousands) 2016   2015   2014 United States $ 367,937   $ 354,433   $ 320,327 Japan 120,160   104,299   108,757 Germany 99,814   94,546   99,714 South Korea 56,790   55,142   55,606 France 49,294   49,444   58,785 Canada 13,284   13,314   14,034 Other European 139,813   145,985   159,011 Other international 141,373   125,590   119,787 Total revenue $ 988,465   $ 942,753   $ 936,021
Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country	Property and equipment by geographic area is as follows:   December 31, (in thousands) 2016   2015 United States $ 43,810   $ 47,971 Europe 4,753   6,808 India 3,033   3,286 Other international 3,081   3,859 Total property and equipment, net $ 54,677   $ 61,924