Note 2. Goodwill and Intangible Assets Goodwill rollforward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill, gross	$ 520,385us-gaap_GoodwillGross	$ 520,628us-gaap_GoodwillGross	$ 521,020us-gaap_GoodwillGross
Accumulated impairment loss	(183,049)	(183,049)	(183,049)
Goodwill, net	337,336us-gaap_Goodwill	337,579us-gaap_Goodwill	337,971us-gaap_Goodwill
Change in foreign currency exchange rates	(243)us-gaap_GoodwillTranslationAdjustments	(392)us-gaap_GoodwillTranslationAdjustments
Logistics [Member]
Goodwill [Line Items]
Goodwill, gross	55,060	55,303	55,695
Accumulated impairment loss	(48,236)	(48,236)	(48,236)
Goodwill, net	6,824	7,067	7,459
Change in foreign currency exchange rates	(243)	(392)
Truckload [Member]
Goodwill [Line Items]
Goodwill, gross	464,598	464,598	464,598
Accumulated impairment loss	(134,813)	(134,813)	(134,813)
Goodwill, net	329,785	329,785	329,785
Change in foreign currency exchange rates	0	0
Corporate and Eliminations [Member]
Goodwill [Line Items]
Goodwill, gross	727	727	727
Accumulated impairment loss	0	0	0
Goodwill, net	727	727	727
Change in foreign currency exchange rates	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB

-Name Accounting Standards Codification

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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