Goodwill And Intangible Assets (Schedule Of Changes In Gross Carrying Amounts Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Line Items]
Goodwill	$ 521,020	$ 521,213	$ 520,765
Accumulated impairment losses	(183,049)	(183,049)	(183,049)
Change in foreign currency exchange rates	(193)	448
Total Goodwill	337,971	338,164	337,716
Logistics
Goodwill [Line Items]
Goodwill	55,695	55,888	55,440
Accumulated impairment losses	(48,236)	(48,236)	(48,236)
Change in foreign currency exchange rates	(193)	448
Total Goodwill	7,459	7,652	7,204
Truckload
Goodwill [Line Items]
Goodwill	464,598	464,598	464,598
Accumulated impairment losses	(134,813)	(134,813)	(134,813)
Change in foreign currency exchange rates	0	0
Total Goodwill	329,785	329,785	329,785
Other
Goodwill [Line Items]
Goodwill	727	727	727
Accumulated impairment losses	0	0	0
Change in foreign currency exchange rates	0	0
Total Goodwill	$ 727	$ 727	$ 727