Liquidity Liquidity (Details) (ABL Facility Credit Agreement [Member], USD $)	9 Months Ended
	Sep. 30, 2012
ABL Facility Credit Agreement [Member]
Debt Instrument, Covenants [Abstract]
Minimum Consolidated EBITDA, September 30, 2012	$ 155,000,000
Minimum Consolidated EBITDA, December 31, 2012	170,000,000
Minimum Consolidated EBITDA, March 31, 2013	200,000,000
Minimum Consolidated EBITDA, June 30, 2013	235,000,000
Minimum Consolidated EBITDA, September 30, 2013	260,000,000
Minimum Consolidated EBITDA, December 31, 2013	275,000,000
Minimum Consolidated EBITDA, March 31, 2014	300,000,000
Minimum Consolidated EBITDA, June 30, 2014	325,000,000
Minimum Consolidated EBITDA, September 30, 2014	355,000,000
Minimum Consolidated EBITDA, December 31, 2014	365,000,000
Maximum Total Leverage Ratio, September 30, 2012	9.6
Maximum Total Leverage Ratio, December 31, 2012	8.6
Maximum Total Leverage Ratio, March 31, 2013	7.4
Maximum Total Leverage Ratio, June 30, 2013	6.5
Maximum Total Leverage Ratio, September 30, 2013	6.0
Maximum Total Leverage Ratio, December 31, 2013	5.7
Maximum Total Leverage Ratio, March 31, 2014	5.1
Maximum Total Leverage Ratio, June 30, 2014	4.8
Maximum Total Leverage Ratio, September 30, 2014	4.6
Maximum Total Leverage Ratio, December 31, 2014	4.4
Minimum Interest Coverage Ratio, September 30, 2012	0.95
Minimum Interest Coverage Ratio, December 31, 2012	1.05
Minimum Interest Coverage Ratio, March 31, 2013	1.20
Minimum Interest Coverage Ratio, June 30, 2013	1.45
Minimum Interest Coverage Ratio, September 30, 2013	1.60
Minimum Interest Coverage Ratio, December 31, 2013	1.65
Minimum Interest Coverage Ratio, March 31, 2014	1.80
Minimum Interest Coverage Ratio, June 30, 2014	1.90
Minimum Interest Coverage Ratio, September 30, 2014	2.10
Minimum Interest Coverage Ratio, December 31, 2014	2.15
Debt Instrument, Covenant, Maximum Annual Asset Sales, Amount	25,000,000
Line of Credit Facility, Maximum Borrowing Capacity	400,000,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 375,900,000