Long-Term Debt (Debt Outstanding) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total	$ 144,875
Current portion of long term debt	(18,000)	$ (7,500)
Long-term debt	126,875	$ 83,750
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total	55,500
Medium-term Notes [Member]
Debt Instrument [Line Items]
Total	$ 89,375