Debt Short-term and Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Senior Notes	$ 210,000	$ 210,000
Convertible Debt	57,500	57,500
Line of Credit Facility, Amount Outstanding	68,300	59,200
Other Long-term Debt	657	1,257
Long-term Debt, Unclassified [Abstract]
Less: unamortized discount	(13,727)	(17,843)
Less: current portion	514	737
Total long-term portion	322,216	309,377
Long-term Debt	$ 322,730	$ 310,114