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

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- References

No definition available.

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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

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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

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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

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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

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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

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- 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

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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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Commitments and Contingencies (Purchase Commitments) (Details) $ in Millions	12 Months Ended
	Dec. 25, 2015 USD ($) locomotives	Dec. 26, 2014 USD ($) locomotives	Dec. 27, 2013 USD ($) locomotives
Unrecorded Unconditional Purchase Obligation [Line Items]
Percentage of locomotive fleet under long-term maintenance program	50.00%
Amounts Paid	$ 233	$ 247	$ 287
Number of Locomotives \| locomotives	2,310	1,886	1,886
Unrecorded Unconditional Purchase Obligation [Abstract]
2016	$ 680
2017	635
2018	307
2019	323
2020	328
Thereafter	4,579
Total	6,852
Locomotive & Maintenance Payments [Member]
Unrecorded Unconditional Purchase Obligation [Abstract]
2016	570
2017	561
2018	287
2019	306
2020	316
Thereafter	4,515
Total	6,555
Other Commitments [Member]
Unrecorded Unconditional Purchase Obligation [Abstract]
2016	110
2017	74
2018	20
2019	17
2020	12
Thereafter	64
Total	$ 297