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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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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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.1)

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-Topic 210

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Amount of loss contingency liability.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

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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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The estimated maximum amount of possible loss from the contingency.

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-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

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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, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	3,015	$ 2,555	$ 2,384	$ 2,225
Unasserted Claim
Asbestos and Personal Injury [Abstract]
Percent of future unasserted asbestos claims to be filed within the next ten years	60.00%
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 60 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 asbestos 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	440
Loss Contingency Accrual [Roll Forward]
Beginning balance	375	387
Accruals	18	18
Payments	(20)	(19)
Ending balance	373	386
Bank Time Deposits and Money Market Funds \| BNSF Insurance Company
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	315		485
Current Liabilities [Member]
Asbestos and Personal Injury [Abstract]
Accrued obligations for asbestos and other personal injury matters, current liabilities	80