Acquisition (Details) (USD $) In Millions, unless otherwise specified				0 Months Ended	3 Months Ended	6 Months Ended		0 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Dec. 17, 2012 State	Dec. 17, 2012 Davenport [Member]	Jun. 30, 2013 Davenport [Member]	Jun. 30, 2013 Davenport [Member]	Jun. 30, 2013 Davenport [Member] Employment agreements [Member]	Dec. 17, 2012 Davenport [Member] Non-competition agreements [Member]	Dec. 17, 2012 Davenport [Member] Customer relationships [Member]
Business Acquisition [Line Items]
Number of states serviced			8
Cash paid at closing for acquisition				$ 34.3
Increase of total consideration						1.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Cash				0.3
Accounts receivable				21.2
Other receivables				3.8
Inventory				20.3
Prepaid expenses / other assets				2.6
Property, plant and equipment				5.3
Intangible assets				2.6				0.7	1.9
Goodwill	23.0	22.8		6.8
Net deferred tax liabilities				(1.3)
Capital lease liability				(10.9)
Other liabilities				(9.9)
Total consideration				40.8
Indemnity holdback for any post-closing liabilities						4.0
Period of time to release indemnity holdback				4 years
Contingent payment amount							0.6
Finite-lived intangible asset, useful life								5 years	10 years
Initial capital leases term						10 years
Capital lease obligations at the current period end					10.6	10.6
Acquisition related costs					$ 0.1	$ 0.3