Long-Term Debt and Credit Facility - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Other notes with interest rates from 3.3% to 6.5%	$ 9,842	$ 9,797
Subtotal	382,717	355,422
Less – Current maturities and notes payable	17,646	17,648
Less – Unamortized loan costs	3,850	4,294
Total	361,221	333,480
Term Note
Debt Instrument [Line Items]
Term note, due October 30, 2020, annualized rates of 2.63% and 2.61%, respectively	$ 336,875	$ 345,625
Current annualized interest rate	2.63%	2.61%
Line of Credit
Debt Instrument [Line Items]
Line of credit, 2.77%	$ 36,000	$ 0
Current annualized interest rate	2.77%
Other notes | Minimum
Debt Instrument [Line Items]
Current annualized interest rate	3.30%	3.30%
Other notes | Maximum
Debt Instrument [Line Items]
Current annualized interest rate	6.50%	6.50%