Other Comprehensive Income Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Before-tax amount [Abstract]
Foreign currency translation adjustment	$ (49,820)	$ 21,992	$ (61,208)	$ 1,343
Net unrealized gain (loss) on derivative instruments designated as cash flow hedges	217	(1,021)	(556)	223
Net hedging loss (gain) reclassified into net income	430	274	1,275	274
Pension plan benefits liability adjustment	141	266	449	(17)
Total other comprehensive income (loss), before tax	(49,032)	21,511	(60,040)	1,823
Tax (provision) benefit [Abstract]
Foreign currency translation adjustment	429	(73)	448	(3,544)
Net unrealized gain (loss) on derivative instruments designated as cash flow hedges	(83)	343	212	(129)
Net hedging loss (gain) reclassified into net income	(164)	(104)	(487)	(104)
Pension plan benefits liability adjustment	(43)	(81)	(136)	5
Total other comprehensive income (loss) tax (provision) benefit	139	85	37	(3,772)
Net-of-tax amount [Abstract]
Foreign currency translation adjustment	(49,391)	21,919	(60,760)	(2,201)
Net unrealized gain (loss) on derivative instruments designated as cash flow hedges	134	(678)	(344)	94
Net hedging loss (gain) reclassified into net income	266	170	788	170
Pension plan benefits liability adjustment	98	185	313	(12)
Total other comprehensive income (loss), net of tax	$ (48,893)	$ 21,596	$ (60,003)	$ (1,949)