The principal amount of new debt issued during the period, excluding premium or discount, if any.

No definition available.

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- Definition

The date, which may be expressed in a variety of ways, of issuance.

+ References

No definition available.

+ Details

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- Definition

The latest date, which may be expressed in a variety of ways, of a range of contractual maturity dates.

+ References

No definition available.

+ Details

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- Definition

The earliest date, which may be expressed in a variety of ways, of a range of contractual maturity dates.

+ References

No definition available.

+ Details

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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 210.5-02.22(a)(1))

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

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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 FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: 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(b),22(b))

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 18

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3291-108585

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 20

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Notes payable and other borrowings - Narrative (Detail) (USD $)	3 Months Ended							1 Months Ended	3 Months Ended			1 Months Ended		3 Months Ended	1 Months Ended
	Mar. 31, 2013 Insurance and Other [Member]	Mar. 31, 2012 Insurance and Other [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member]	Mar. 31, 2012 Railroad, Utilities and Energy [Member]	Mar. 31, 2013 Finance and Financial Products [Member]	Mar. 31, 2012 Finance and Financial Products [Member]	Mar. 31, 2013 Berkshire Hathaway (Parent) [Member] Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]	Jan. 31, 2013 Berkshire Hathaway (Parent) [Member] Senior Notes [Member] Insurance and Other [Member]	Mar. 31, 2013 Berkshire Hathaway (Parent) [Member] Senior Notes [Member] Insurance and Other [Member]	Mar. 31, 2013 Berkshire Hathaway (Parent) [Member] Senior Notes [Member] Insurance and Other [Member] Minimum [Member]	Mar. 31, 2013 Berkshire Hathaway (Parent) [Member] Senior Notes [Member] Insurance and Other [Member] Maximum [Member]	Feb. 28, 2013 Berkshire Hathaway (Parent) [Member] Senior Notes Due 2013 and 2014 [Member] Insurance and Other [Member]	Mar. 31, 2013 BNSF [Member] Debentures [Member] Railroad, Utilities and Energy [Member]	Mar. 31, 2013 BNSF [Member] Debentures [Member] Railroad, Utilities and Energy [Member]	Mar. 31, 2013 BNSF [Member] Debentures Due 2023 at 3% [Member] Railroad, Utilities and Energy [Member]	Mar. 31, 2013 BNSF [Member] Debentures Due 2043 at 4.45% [Member] Railroad, Utilities and Energy [Member]	Jan. 31, 2013 Berkshire Hathaway Finance Corporation [Member] Senior Notes [Member] Finance and Financial Products [Member]	Mar. 31, 2013 Berkshire Hathaway Subsidiaries [Member] Line of Credit and Commercial Paper Facilities [Member]
Debt Instrument [Line Items]
Principal amount of debt issued								$ 2,600,000,000					$ 1,500,000,000		$ 700,000,000	$ 800,000,000	$ 500,000,000
Issuance date									January 2013					March 2013
Debt Instrument, Interest Rate, Stated Percentage										0.80%	4.50%				3.00%	4.45%
Maturity date, range, start									2016
Maturity date, range, end									2043
Repayment of long-term debt	2,691,000,000	1,791,000,000	152,000,000	160,000,000	605,000,000	333,000,000						2,600,000,000
Repayment of debt																	500,000,000
Unused lines of credit available																		4,700,000,000
Guarantee obligation							$ 4,400,000,000