Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Senior debt:
Total debt	$ 175,000	$ 161,500
Less: Current maturities	(17,000)	(17,000)
Total long-term debt, net of current maturities	158,000	144,500
Revolving credit facility [Member]
Senior debt:
Total debt	22,000	0
Term loans [Member]
Senior debt:
Total debt	$ 153,000	$ 161,500