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Increase in personal injury expense

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Length in Years for 60% of Future Unasserted Asbestos Claims to be Filed

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Length in Years for 80 Percent of Future Unasserted Asbestos Claims to be Filed

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Length in Years for 95 Percent of Future Unasserted Claims to be Filed

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No change was recorded in personal injury expense

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Percent of Future Unasserted Asbestos Claims to be Filed Within the Next Fifteen Years

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Percent of Future Unasserted Asbestos Claims To be Filed Within the Next Ten Years

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Percent of Future Unasserted Asbestos Claims to be Filed Within the Next Twenty-five Years

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- Definition

Percent of total cost of future asbestos claims

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Percent of total number of future asbestos claims

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of loss contingency liability.

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-Name Accounting Standards Codification
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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of payments made reducing loss contingency liability.

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Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The estimated maximum amount of possible loss from the contingency.

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The estimated minimum amount of possible loss from the contingency.

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Commitments and Contingencies - Personal Injury (Details) - USD ($) $ in Millions	9 Months Ended			12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loss Contingency Accrual [Roll Forward]
Beginning balance	$ 140			$ 140
Ending balance				135	$ 140
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents				$ 2,329	2,384	$ 2,225	$ 1,794
Asbestos, non-malignant [Member]
Asbestos and Personal Injury [Abstract]
Percent of total number of future asbestos claims				80.00%
Percent of total cost of future asbestos claims				45.00%
Unasserted Claim
Asbestos and Personal Injury [Abstract]
Percent of future unasserted asbestos claims to be filed within the next ten years				65.00%
Percent of future unasserted asbestos claims to be filed within the next fifteen years				80.00%
Percent of future unasserted asbestos claims to be filed within the next twenty-five years				95.00%
Length in Years for 65 Percent of Future Unasserted Asbestos Claims to be Filed				10 years
Length in Years for 80 Percent of Future Unasserted Asbestos Claims to be Filed				15 years
Length in Years for 95 Percent of Future Unasserted Claims to be Filed				25 years
Personal Injury
Asbestos and Personal Injury [Abstract]
Future costs to settle personal injury claims, minimum				$ 330
Future costs to settle personal injury claims, maximum				445
Loss Contingency Accrual [Roll Forward]
Beginning balance	375	$ 387	$ 462	375	387	462
Accruals				81	61	21
Payments				(81)	(73)	(96)
Ending balance				375	375	$ 387
Time Deposits, and Money Market Funds [Member] \| BNSF Insurance Company
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents				410	485
Current Liabilities [Member]
Asbestos and Personal Injury [Abstract]
Accrued obligations for asbestos and other personal injury matters, current liabilities				$ 85	$ 80
Asbestos Issue [Member]
Asbestos and Personal Injury [Abstract]
Increase in personal injury expense	$ 5
Decrease in personal injury expense		$ 2
No change was recorded in personal injury expense			$ 0