Debt (Schedule of Long-term Debt) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term Debt	$ 494,059	$ 502,513
Long-term Debt, Current Maturities	(429)	(2,847)
Long-term Debt, Excluding Current Maturities	493,630	499,666
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	496	2,927
Senior Notes [Member] | Senior Notes, Issued [Member]
Debt Instrument [Line Items]
Long-term Debt	423,563	419,586
Revolving Credit Facility [Member] | Senior secured revolving credit facility [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 70,000	$ 80,000