CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Foreign currency translation adjustments, deferred income taxes	$ (4,977)	$ 4,542	$ (8,554)	$ 2,892
Net gain (loss) on cash flow hedging instruments, deferred income taxes	401	984	415	(538)
Pension liability adjustments, deferred income taxes	(517)	(469)	(1,034)	(939)
Unrealized gain (loss) on marketable securities, deferred income taxes	$ (2)	$ (1)	$ 2	$ 3