Stockholders Equity (Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Estimated tax rate	40.00%
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at December 31, 2012	$ 12,569
Unrealized (losses) gains, arising during the period	(11,697)
Taxes on unrealized (losses) gains, arising during the period	4,681
Balance at September 30, 2013	5,553
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at December 31, 2012	10,800
Unrealized (losses) gains, arising during the period	(15,362)
Taxes on unrealized (losses) gains, arising during the period	6,146
Balance at September 30, 2013	1,584
Forward Contract Foreign Currency [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at December 31, 2012	1,769
Unrealized (losses) gains, arising during the period	3,665
Taxes on unrealized (losses) gains, arising during the period	(1,465)
Balance at September 30, 2013	$ 3,969