Long-term Debt Activity (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 435,800	$ 148,000
Current maturities of long-term debt	29,676	10,431
Less unamortized discounts	7,100	2,400
Long-term debt, less current maturities	398,975	135,232
Senior Loans [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 387,200	132,000
Long-term Debt, Weighted Average Interest Rate	4.04%
Junior Loans [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 48,600	$ 16,000
Long-term Debt, Weighted Average Interest Rate	6.89%