CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Foreign currency translation adjustments, deferred income taxes	$ (3,747)	$ 5,322	$ (855)	$ 4,862
Net gain (loss) on cash flow hedging instruments, deferred income taxes	(799)	(458)	(1,337)	210
Pension liability adjustments, deferred income taxes	(2,384)	(2,057)	(3,344)	(2,130)
Unrealized gain on marketable securities, deferred income taxes	$ 4	$ (1)	$ 7	$ (3)