Long-Term Debt (Narrative) (Details) (USD $)	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended			6 Months Ended
	Jun. 30, 2014 Senior Credit Agreement	Mar. 31, 2013 Senior Subordinated 8% Notes, Due December 1, 2015	Jun. 30, 2014 Revolving Credit Facility	Mar. 31, 2013 Senior Subordinated 6.25% Notes	Jun. 30, 2014 Senior Subordinated 6.25% Notes	Jan. 31, 2013 Senior Subordinated 6.25% Notes	Jun. 30, 2014 London Interbank Offering Rate (LIBOR) Minimum Revolving Credit Facility	Jun. 30, 2014 London Interbank Offering Rate (LIBOR) Maximum Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, issuance date				Jan. 31, 2013
Debt instrument, issued value		$ 204,000,000				$ 210,000,000
Senior Subordinated Notes, interest rate		8.00%		6.25%	6.25%
Debt instrument, maturity date				Feb. 01, 2021
Loss on extinguishment of debt		7,166,000
Prepayment premium for extinguishment of debt		3,702,000
Write-off deferred financing fees		2,199,000
Write off of debt discount		1,265,000
Placement and other fees				3,755,000
Maximum borrowing capacity under the revolving credit facility	200,000,000
Revolving credit facility, increase, additional borrowings	250,000,000
Revolving credit facility termination date			Oct. 10, 2016
LIBOR floor, plus							2.00%	2.50%
Revolving credit facility, annual commitment fee			0.375%
Standby letters of credit	21,856,000
Revolving credit facility, availability amount			$ 118,438,000
Fixed charge coverage ratio	125.00%