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Number of depreciable asset categories to account for depreciation expense for the railroad assets that are depreciated under the group life method.

+ References

No definition available.

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- Definition

Percentage of total gross assets depreciated under the group-life method of accounting. Does not include other assets which are depreciated on a straight line basis.

+ References

No definition available.

+ Details

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- Definition

Percentage of labor costs relating to the deconstruction of old track based upon an analysis of track replacement process.

+ References

No definition available.

+ Details

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- Definition

Percentage of labor costs relating to the installation of new track based upon an analysis of track replacement process.

+ References

No definition available.

+ Details

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- Definition

The frequency with which life studies are required, by Surface Transporation Board (STB) to be performed.

+ References

No definition available.

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- Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: 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

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

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-Paragraph 1

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Properties (Railroad Assets, Non-Railroad Assets, and Capital Expenditure) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 26, 2014	Dec. 27, 2013	Dec. 28, 2012
Railroad Assets [Abstract]
Percentage of assets depreciated under the group-life method	85.00%
Total fixed assets	$ 39,343us-gaap_PropertyPlantAndEquipmentGross	$ 37,184us-gaap_PropertyPlantAndEquipmentGross
Annual depreciation expense	1,151us-gaap_Depreciation	1,104us-gaap_Depreciation	1,059us-gaap_Depreciation
Capital Expenditures [Abstract]
Percentage of labor costs relating to the deconstruction of old track (In hundredths)	20.00%
Percentage of labor costs relating to the installation of new track (In hundredths)	80.00%
Road - Total [Member]
Railroad Assets [Abstract]
Total fixed assets	26,125	24,618
Life studies, frequency period	6 years
Road - Ties [Member]
Railroad Assets [Abstract]
Total fixed assets	4,807	4,534
Number of depreciable asset categories for railroad assets	18
Road - System Roadway Machinery [Member]
Railroad Assets [Abstract]
Total fixed assets	4,070	3,654
Road - Grading [Member]
Railroad Assets [Abstract]
Total fixed assets	2,460	2,425
Total Equipment [Member]
Railroad Assets [Abstract]
Total fixed assets	10,108	9,764
Life studies, frequency period	3 years
Equipment - Work Equipment and Other [Member]
Railroad Assets [Abstract]
Total fixed assets	1,828	1,666
Abnormal gain (loss) on operating property [Member]
Railroad Assets [Abstract]
Abnormal gains and losses	0	65	104
Gain (loss) on non-operating property [Member]
Railroad Assets [Abstract]
Abnormal gains and losses		57
Minimum [Member]
Railroad Assets [Abstract]
Number of depreciable asset categories for railroad assets	130
Minimum [Member] \| Road - Total [Member]
Railroad Assets [Abstract]
Estimated useful life	8 years	6 years
Minimum [Member] \| Road - System Roadway Machinery [Member]
Railroad Assets [Abstract]
Estimated useful life	8 years
Minimum [Member] \| Total Equipment [Member]
Railroad Assets [Abstract]
Estimated useful life	3 years	5 years
Minimum [Member] \| Technology Assets [Member]
Railroad Assets [Abstract]
Estimated useful life	3 years
Maximum [Member] \| Road - Total [Member]
Railroad Assets [Abstract]
Estimated useful life	90 years	80 years
Maximum [Member] \| Road - Grading [Member]
Railroad Assets [Abstract]
Estimated useful life	90 years
Maximum [Member] \| Total Equipment [Member]
Railroad Assets [Abstract]
Estimated useful life	38 years	38 years
Maximum [Member] \| Equipment - Work Equipment and Other [Member]
Railroad Assets [Abstract]
Estimated useful life	38 years
SunRail Transaction - Sale of Corridor [Member]
Railroad Assets [Abstract]
Abnormal gains and losses		$ 43	$ 94