Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Senior debt:
Total debt	$ 311,114	$ 192,640
Less: Current maturities	(13,125)	(10,938)
Total long-term debt, net of current maturities	297,989	181,702
Revolving credit facility [Member]
Senior debt:
Total debt	144,864	22,015
Term loans [Member]
Senior debt:
Total debt	$ 166,250	$ 170,625