Indebtedness And Borrowing Facilities (Details) (USD $)	3 Months Ended		9 Months Ended					3 Months Ended	0 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 2016 Credit Facility [Member]	Sep. 30, 2012 2016 Term Loan [Member]	Sep. 30, 2012 2017 Term Loan [Member] item	Sep. 30, 2012 2013 Convertible Notes [Member]	May 03, 2011 2019 Notes [Member]	Sep. 30, 2012 Minimum [Member] 2016 Credit Facility [Member]	Sep. 30, 2012 Bank's Prime Rate [Member] 2016 Term Loan [Member]	Sep. 30, 2012 Bank's Prime Rate [Member] Minimum [Member] 2016 Credit Facility [Member]	Sep. 30, 2012 Bank's Prime Rate [Member] Maximum [Member] 2016 Credit Facility [Member]	Sep. 30, 2012 LIBOR Rate [Member] 2016 Term Loan [Member]	Sep. 30, 2012 LIBOR Rate [Member] Minimum [Member] 2016 Credit Facility [Member]	Sep. 30, 2012 LIBOR Rate [Member] Maximum [Member] 2016 Credit Facility [Member]	Sep. 30, 2012 Notes Repurchased [Member] 2013 Convertible Notes [Member]
Debt Instrument [Line Items]
Term loans available under credit facility					$ 50,000,000
Increase in term loans available under credit facility					25,000,000
Maximum borrowing capacity available under asset-based revolving credit agreement					450,000,000
Asset-based revolving credit facility, maturity date					Jan. 04, 2016
Percentage points added to stated interest rate											3.50%	1.25%	1.75%	4.50%	2.25%	2.75%
Commitment fee on unused amount					0.50%
The amount expressed as a percentage of borrowing base, that availability under the credit facility will be reduced if not in compliance with a fixed charge coverage ratio					12.50%
The amount expressed in dollars, that availability under the credit facility will be reduced if not in compliance with a fixed charge coverage ratio					56,300,000					45,000,000
Amount of borrowings unavailable due to availability block					45,000,000
Asset borrowing base less availability block					438,800,000
Line of credit facility, current borrowing capacity					393,800,000
Asset borrowing base					483,800,000
Letters of credit issued					2,200,000
Availability under facility after issuance of letter of credit					391,600,000
Net proceeds from term loan						48,500,000	95,600,000
Fees and expenses incurred						1,500,000	4,400,000
Interest rate of notes							10.00%	2.50%	6.75%
Maturity date							Sep. 27, 2017	Aug. 01, 2013	May 15, 2019
Minimum interest rate on term loan after LIBOR adjustment							11.00%
Quarterly amortization payments on debt instrument							1,667,500
Threshold on payments made that are subject to prepayment premiums							10,000,000
Prepayment premium percentage in year one							5.00%
Prepayment premium percentage in year two							4.00%
Prepayment premium percentage in year three							3.00%
Prepayment premium percentage in year four							2.00%
Fixed charge coverage ratio required under covenant terms							1.0
Amount of debt repurchased								88,100,000
Amount paid for debt repurchase								84,800,000
Principal repayments of long-term debt			88,100,000	306,800,000				84,600,000
Accured and unpaid interest																	200,000
Loss on extinguishment of debt	(600,000)		(600,000)	(4,100,000)				(600,000)
Aggregate amount of debt outstanding								286,900,000
Number of lenders							2
Term loans borrowed						50,000,000	100,000,000
Debt instrument, issuance date									May 03, 2011
Notes issued, amount									$ 325,000,000