Long-Term Debt (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
	Mar. 31, 2013	Sep. 30, 2015	Dec. 31, 2014	Jan. 31, 2013
Debt Instrument [Line Items]
Less unamortized debt issuance costs		$ 2,986,000	$ 3,689,000
Senior Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity under the revolving credit facility		200,000,000
Revolving credit facility, increase, additional borrowings		250,000,000
Standby letters of credit		$ 19,991,000
Fixed charge coverage ratio		125.00%
Senior Subordinated 8% Notes, Due December 1, 2015
Debt Instrument [Line Items]
Debt instrument, issued value	$ 204,000,000
Senior Subordinated Notes, interest rate	8.00%
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
Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility, annual commitment fee		0.375%
Revolving credit facility, availability amount		$ 88,164,000
Senior Subordinated 6.25% Notes
Debt Instrument [Line Items]
Debt instrument, issued value				$ 210,000,000
Senior Subordinated Notes, interest rate	6.25%	6.25%
Less unamortized debt issuance costs	$ 3,755,000
London Interbank Offering Rate (LIBOR) | Minimum | Revolving credit facility
Debt Instrument [Line Items]
LIBOR floor, plus		2.00%
London Interbank Offering Rate (LIBOR) | Maximum | Revolving credit facility
Debt Instrument [Line Items]
LIBOR floor, plus		2.50%