Debt -Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Carrying value of debt	$ 258,094	$ 265,050
Current portion of long-term debt	(20,625)	(15,000)
Total long-term debt, net	237,469	250,050
Senior Subordinated Convertible Notes 2010
Debt Instrument [Line Items]
Carrying value of debt	134,344	130,050
2012 Credit Agreement | Revolving Loan
Debt Instrument [Line Items]
Carrying value of debt	0	0
2012 Credit Agreement | Term Loan
Debt Instrument [Line Items]
Carrying value of debt	$ 123,750	$ 135,000