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v2.4.1.9

Accounting Changes Accounting Changes (Details) (USD $) In Millions, except Per Share data, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Property, Plant and Equipment [Line Items] |  |  |
Depreciation, Nonproduction | $ 273.5 us-gaap_DepreciationNonproduction | $ 255.0 us-gaap_DepreciationNonproduction | $ 237.4 us-gaap_DepreciationNonproduction
Service Life [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciation, Nonproduction | 21.9 us-gaap_DepreciationNonproduction / us-gaap_ChangeInAccountingEstimateByTypeAxis = us-gaap_ServiceLifeMember |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income | $ 14.0 us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfChangeOnNetIncome / us-gaap_ChangeInAccountingEstimateByTypeAxis = us-gaap_ServiceLifeMember |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share | $ 0.31 us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfChangeOnDilutedEarningsPerShare / us-gaap_ChangeInAccountingEstimateByTypeAxis = us-gaap_ServiceLifeMember |  |
Railcars [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Average Increase (Decrease) in Estimated Railcar Useful Life | 2 years 2 months 12 days |  |
Railcars [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property, Plant and Equipment, Useful Life | 27 years | 30 years |
Railcars [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property, Plant and Equipment, Useful Life | 42 years | 38 years |

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- Definition The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
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