Segment Information (Narrative) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($) customer	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) customer	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) customer segment	Dec. 31, 2014 USD ($) customer	Dec. 31, 2013 USD ($) customer
Concentration Risk [Line Items]
Net revenues | $	$ 904,763	$ 813,270	$ 796,759	$ 760,802	$ 851,483	$ 758,994	$ 781,560	$ 750,819	$ 3,275,594	$ 3,142,856	$ 2,918,434
Number of reportable segments | segment									2
Percentage of international revenues accounting for the Company's net revenues									43.10%	45.20%	45.40%
US to International Revenues
Concentration Risk [Line Items]
Net revenues | $									$ 180,200	$ 193,800	$ 215,300
Net revenues | Customer concentration risk
Concentration Risk [Line Items]
Number of customers meeting concentration risk threshold | customer	0								0
Ingram Micro | Net revenues | Customer concentration risk
Concentration Risk [Line Items]
Number of customers meeting concentration risk threshold | customer					1					1	1
Concentration risk percentage										13.00%	14.00%