Operating Leases (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Leases, Operating [Abstract]
Initial lease term of certain distribution centers and manufacturing and store locations, minimum (in months)	1 month
Initial lease term of certain distribution centers and manufacturing and store locations, maximum (in months)	60 months
Initial lease terms of most store locations, minimum (in months)	36 months
Initial lease terms of most store locations, maximum (in months)	48 months
Leasehold improvements, net book value	$ 2,180
Amortization period of leasehold improvements on operating leases (in months)	36 months
Terms of semi-tractor leases (in months)	36 months
Term of non-cancellable pick-up leases (in years)	1 year
Renewal options for non-cancellable pick-up leases, maximum (in months)	72 months
Average pick-up lease term, minimum (in months)	28 months
Average pick-up lease term, maximum (in months)	36 months
Aggregate residual value guarantee	43,654
Loss on disposal reserve	$ 200