Segment Reporting (Details Textual) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Segments	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting (Textual) [Abstract]
Number of reportable business segments	2
Depreciation expense	$ 939,677	$ 872,262	$ 833,841
Acquisitions	5,113	361,921	211,897
Supply Chain Solutions [Member]
Segment Reporting (Textual) [Abstract]
Depreciation expense	28,275	29,118	20,285
Central support service assets depreciation expense allocated to other business segments [Member]
Segment Reporting (Textual) [Abstract]
Depreciation expense	$ 12,000	$ 9,000	$ 9,000
Automotive industry [Member] | Supply Chain Solutions [Member]
Segment Reporting (Textual) [Abstract]
Percentage of total revenue	30.00%	27.00%	31.00%