Long-Term Debt - Schedule of Long-Term Debt (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Equipment, Long-Term Notes Payable [Member]	Jan. 31, 2014 Equipment, Long-Term Notes Payable [Member]	Dec. 31, 2013 Equipment, Long-Term Notes Payable [Member]	Jun. 30, 2014 Notes Payable [Member]	Dec. 31, 2013 Notes Payable [Member]	Dec. 20, 2013 Notes Payable [Member]	Jun. 30, 2014 Term Facility [Member]	Dec. 31, 2013 Term Facility [Member]	Jun. 30, 2014 Term Facility [Member] Wholly-owned subsidiary [Member]	Dec. 31, 2013 Term Facility [Member] Wholly-owned subsidiary [Member]	Jun. 30, 2014 Revolving Facility [Member]	Dec. 31, 2013 Revolving Facility [Member]	Jun. 30, 2014 Revolving Facility [Member] Wholly-owned subsidiary [Member]
Debt Instrument [Line Items]
Total debt	$ 168,268,000	$ 155,895,000	$ 2,678,000	$ 2,700,000	$ 0	$ 5,761,000	$ 5,531,000		$ 149,829,000	$ 150,364,000			$ 10,000,000	$ 0
Less—Amounts due within one year	(2,461,000)	(1,550,000)
Long-term debt	165,807,000	154,345,000
Credit facility, maximum borrowing capacity											155,000,000	155,000,000			25,000,000
Debt instrument, stated interest rate				7.50%				8.50%			9.25%
Debt instrument, unamortized discount											$ 4,400,000	$ 4,600,000