Line-of-Credit and Long-term Debt - Components of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Long-term debt consists of:
Long-term debt	$ 78,298	$ 81,309
Less line-of-credit and current maturities of long-term debt	(4,209)	(7,094)
Long-term debt, less current portion	74,089	74,215
Revolving line of credit
Long-term debt consists of:
Long-term debt	3,960	6,850
Note payable to a bank
Long-term debt consists of:
Long-term debt	$ 74,338	$ 74,459