Debt Short-term and Long-term Debt (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 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 62,000 59,200
Other Long-term Debt 993 1,257
Long-term Debt, Gross 330,493 327,957
Long-term Debt, Unclassified [Abstract]    
Less: unamortized discount (16,520) (17,843)
Less: current portion (734) (737)
Total long-term portion 313,239 309,377
Long-term Debt $ 313,973 $ 310,114