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

Reporting Entity [Axis]

0000851205 (http://www.sec.gov/CIK)

Payables and Accruals [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Payables and Accruals [Abstract]
Constituents of Accrued Expenses	Accrued expenses consisted of the following (in thousands):   December 31,   2016   2015 Company bonuses $ 11,462   $ 4,895 Salaries, commissions, and payroll taxes 7,193   4,859 Vacation 4,860   4,482 Warranty obligations 4,335   4,174 Foreign retirement obligations 3,388   3,249 Other 11,301   11,613   $ 42,539   $ 33,272
Changes in Warranty Obligations	The changes in the warranty obligation were as follows (in thousands): Balance as of December 31, 2014 $ 4,086 Provisions for warranties issued during the period 4,383 Fulfillment of warranty obligations (3,873 ) Foreign exchange rate changes (422 ) Balance as of December 31, 2015 4,174 Provisions for warranties issued during the period 3,001 Fulfillment of warranty obligations (2,689 ) Foreign exchange rate changes (151 ) Balance as of December 31, 2016 $ 4,335