Fair Value Measurement (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value Measurement
Long-term debt	$ (253,400)	$ (288,666)
Carrying Amount
Fair Value Measurement
Cash and cash equivalents	18,196	23,158
Total Fair Value
Fair Value Measurement
Cash and cash equivalents	18,196	23,158
Senior Credit Facility, net of discount
Fair Value Measurement
Long-term debt	(251,010)	(286,672)
Senior Credit Facility, net of discount | Carrying Amount
Fair Value Measurement
Long-term debt	(251,010)	(286,672)
Senior Credit Facility, net of discount | Total Fair Value
Fair Value Measurement
Long-term debt	(251,010)	(286,672)
Other obligations
Fair Value Measurement
Long-term debt	(2,390)	(1,994)
Other obligations | Carrying Amount
Fair Value Measurement
Long-term debt	(2,390)	(1,994)
Other obligations | Total Fair Value
Fair Value Measurement
Long-term debt	$ (2,390)	$ (1,994)