Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term Debt	$ 395,000	$ 455,080
Long-term Debt, Current Maturities	0	(27)
Long-term Debt, Excluding Current Maturities	395,000	455,053
Senior Notes [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt	300,000	300,000
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	0	80
Revolving Credit Facility [Member] | Senior secured revolving credit facility [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 95,000	$ 155,000