Debt Debt (Schedule of Maturities of Long-term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	$ 814
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	842
2020	871
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Four	188,475
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Five	417,931
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	518,973
Long-term Debt, Gross	1,127,906
Debt Instrument, Unamortized Discount	(5,060)
Less: unamortized loan costs	(11,554)
Debt, Long-term and Short-term, Combined Amount	$ 1,111,292	$ 1,115,981