Percentage of ownership to be acquired in a potential business acquisition.

No definition available.

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- Definition

The aggregate cash committed to be paid for a potential business acquisition.

+ References

No definition available.

+ Details

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- Definition

The percentage of securities that each class of warrants or rights give the holder the right to purchase from the issuer.

+ References

No definition available.

+ Details

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- Definition

Commitment to purchase equity securities of an investee.

+ References

No definition available.

+ Details

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- Definition

The recovery percentage of the entity's surety bond claim losses that its joint venture partner is obligated to pay.

+ References

No definition available.

+ Details

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- Definition

The stated value of shares to be acquired.

+ References

No definition available.

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- Definition

Exercise price of the warrants.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column A

+ Details

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(a)(3))

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(2))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Subparagraph a(3)

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 2

-Article 9

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Balance Type:	credit
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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of stores.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

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Contingencies and Commitments - Narrative (Detail) In Billions, except Per Share data, unless otherwise specified			9 Months Ended			0 Months Ended
	Sep. 30, 2014 Berkadia Commercial Mortgage (investee) [Member] USD ($)	Sep. 30, 2014 Leucadia National Corporation (venture partner) [Member] Berkadia Commercial Mortgage (investee) [Member]	Sep. 30, 2014 Berkshire Hathaway Insurance Group [Member]	Sep. 30, 2014 Surety bonds [Member] Berkshire Hathaway Insurance Group [Member] USD ($)	Aug. 26, 2014 Purchase Agreement [Member] Perpetual Preferred Stock [Member] Newly Formed Entity- Ultimate Parent Company of Burger King and Tim Hortons [Member] USD ($)	Aug. 26, 2014 Purchase Agreement [Member] Common Stock Warrants [Member] Newly Formed Entity- Ultimate Parent Company of Burger King and Tim Hortons [Member] USD ($)	Aug. 26, 2014 Purchase Agreement [Member] Perpetual Preferred Stock and Warrants [Member] Newly Formed Entity- Ultimate Parent Company of Burger King and Tim Hortons [Member] USD ($)	May 01, 2014 Purchase Agreement [Member] Berkshire Hathaway Energy [Member] AltaLink [Member] USD ($)	May 01, 2014 Purchase Agreement [Member] Berkshire Hathaway Energy [Member] AltaLink [Member] CAD	Oct. 01, 2014 Subsequent Event [Member] Purchase Agreement [Member] Insurance and Certain Real Estate Businesses [Member] Van Tuyl Group [Member]	Oct. 01, 2014 Subsequent Event [Member] Purchase Agreement [Member] Auto Dealerships [Member] Van Tuyl Group [Member] State Store
Commitments and Contingencies [Line Items]
Voting interest in investee	50.00%	50.00%
Guarantee obligation, maximum amount of exposure				$ 2.5
Reimbursement rate from joint venture partner of Company's surety bond claim losses			50.00%
Commercial paper outstanding	2.47
Ownership percentage to be acquired								100.00%	100.00%	100.00%
Cash committed to be paid for a potential business acquisition								2.9	3.2
Stated value of equity securities to be acquired					3
Percentage of common shares that can be purchased						1.75%
Commitment to purchase equity securities of an investee							$ 3
Exercise price for warrant to be acquired, per share						$ 0.01
Number of dealers in auto dealership group											78
Number of states with auto dealership locations											10