Goodwill And Intangible Assets (Schedule Of Changes In Gross Carrying Amounts Of Goodwill) (Details) (USD $) In Thousands	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Sep. 30, 2011
Goodwill [Line Items]
Goodwill	$ 520,699	$ 520,293	$ 521,237
Accumulated impairment losses	(183,049)	(166,635)	(183,049)
Total Goodwill	337,650	353,658	338,188
Impairment charge		(16,414)
Change in foreign currency exchange rates	538	406
Logistics [Member]
Goodwill [Line Items]
Goodwill	55,374	54,968	55,912
Accumulated impairment losses	(48,236)	(31,822)	(48,236)
Total Goodwill	7,138	23,146	7,676
Impairment charge		(16,414)
Change in foreign currency exchange rates	538	406
Truckload [Member]
Goodwill [Line Items]
Goodwill	464,598	464,598	464,598
Accumulated impairment losses	(134,813)	(134,813)	(134,813)
Total Goodwill	329,785	329,785	329,785
Impairment charge
Change in foreign currency exchange rates
Other [Member]
Goodwill [Line Items]
Goodwill	727	727	727
Accumulated impairment losses
Total Goodwill	727	727	727
Impairment charge
Change in foreign currency exchange rates