Number of locomotives under the long-term maintenance program.

No definition available.

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- Definition

Percentage of locomotive fleet currently covered under a long-term maintenance program.

+ References

No definition available.

+ Details

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- Definition

Maintenance costs incurred and directly related to services rendered by an entity during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Details

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Commitments and Contingencies (Purchase Commitments) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 26, 2014 locomotives	Dec. 27, 2013 locomotives	Dec. 28, 2012 locomotives
Unrecorded Unconditional Purchase Obligation [Line Items]
Percentage of Locomotive Fleet Under Long-Term Maintenance Program	42.00%
Amounts Paid	$ 247us-gaap_CostOfServicesMaintenanceCosts	$ 287us-gaap_CostOfServicesMaintenanceCosts	$ 287us-gaap_CostOfServicesMaintenanceCosts
Number of locomotives under the long term maintenance plan	1,886	1,886	1,899
Unrecorded Unconditional Purchase Obligation [Abstract]
2014	963
2015	496
2016	190
2017	181
2018	170
Thereafter	1,272
Total	3,272
Locomotive & Maintenance Payments [Member]
Unrecorded Unconditional Purchase Obligation [Abstract]
2014	727
2015	474
2016	177
2017	169
2018	159
Thereafter	1,203
Total	2,909
Other Commitments [Member]
Unrecorded Unconditional Purchase Obligation [Abstract]
2014	236
2015	22
2016	13
2017	12
2018	11
Thereafter	69
Total	$ 363