CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Foreign currency translation adjustments, deferred income taxes	$ (3,577)	$ (1,650)
Net gain (loss) on cash flow hedging instruments, deferred income taxes	14	(1,522)
Pension liability adjustments, deferred income taxes	(1,574)	(3,091)
Unrealized loss on marketable securities, deferred income taxes	$ 4	$ 4