Shareholders' Equity Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Before-tax amount [Abstract]
Foreign currency translation adjustment	$ 10,458	$ (60,773)
Net unrealized gain (loss) on derivative instruments designated as cash flow hedges	(4,513)	(597)
Net hedging loss reclassified into net income	286	412
Pension benefit obligation adjustment	(455)	511
Total other comprehensive income (loss), before tax	5,776	(60,447)
Tax (provision) benefit [Abstract]
Foreign currency translation adjustment	(352)	454
Net unrealized gain (loss) on derivative instruments designated as cash flow hedges	1,731	228
Net hedging loss reclassified into net income	(110)	(157)
Pension benefit obligation adjustment	137	(7)
Total other comprehensive income (loss) tax (provision) benefit	1,406	518
Net-of-tax amount [Abstract]
Foreign currency translation adjustment	10,106	(60,319)
Net unrealized gain (loss) on derivative instruments designated as cash flow hedges	(2,782)	(369)
Net hedging loss (gain) reclassified into net income	176	255
Pension benefit obligation adjustment	(318)	504
Total other comprehensive income (loss), net of tax	(7,182)	59,929
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Net-of-tax amount [Abstract]
Total other comprehensive income (loss), net of tax	(10,106)	60,319
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Net-of-tax amount [Abstract]
Total other comprehensive income (loss), net of tax	$ 2,606	$ 114