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

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the 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 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

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

-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.

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Notes payable and other borrowings - Narrative (Detail) (USD $)				1 Months Ended
	Sep. 30, 2014 Berkshire Hathaway Subsidiaries [Member] Line of Credit and Commercial Paper Facilities [Member]	Sep. 30, 2014 Berkshire Hathaway Energy Company and Subsidiaries [Member] Line of Credit and Commercial Paper Facilities [Member]	Sep. 30, 2014 Berkshire Hathaway (Parent) [Member] Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]	Jul. 31, 2014 Berkshire Hathaway Finance Corporation [Member] Senior Notes [Member] Finance and Financial Products [Member]	Jan. 31, 2014 Berkshire Hathaway Finance Corporation [Member] Senior Notes [Member] Finance and Financial Products [Member]	Jul. 31, 2014 Berkshire Hathaway Finance Corporation [Member] Senior Notes Due 2017, Floating Rate [Member] Finance and Financial Products [Member]	Jan. 31, 2014 Berkshire Hathaway Finance Corporation [Member] Senior Notes Due 2017, Floating Rate [Member] Finance and Financial Products [Member]	Jan. 31, 2014 Berkshire Hathaway Finance Corporation [Member] Senior Notes Due 2018 at 2% [Member] Finance and Financial Products [Member]	Aug. 31, 2014 BNSF [Member] Debentures [Member] Railroad, Utilities and Energy [Member]	Mar. 31, 2014 BNSF [Member] Debentures [Member] Railroad, Utilities and Energy [Member]	Mar. 31, 2014 BNSF [Member] Debentures Due 2024 at 3.75% [Member] Railroad, Utilities and Energy [Member]	Mar. 31, 2014 BNSF [Member] Debentures Due 2044 at 4.9% [Member] Railroad, Utilities and Energy [Member]	Aug. 31, 2014 BNSF [Member] Debentures Due 2024 at 3.4% [Member] Railroad, Utilities and Energy [Member]	Aug. 31, 2014 BNSF [Member] Debentures Due 2044 at 4.5% [Member] Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued					$ 750,000,000	$ 400,000,000	$ 650,000,000	$ 100,000,000	$ 1,500,000,000	$ 1,500,000,000	$ 500,000,000	$ 1,000,000,000	$ 700,000,000	$ 800,000,000
Debt instrument, interest rate, stated percentage								2.00%			3.75%	4.90%	3.40%	4.55%
Repayment of debt				400,000,000	750,000,000
Unused lines of credit available	7,200,000,000	4,100,000,000
Guarantee obligation			$ 3,800,000,000