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

No definition available.

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

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

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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))

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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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Notes payable and other borrowings - Narrative (Detail) (USD $)	1 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 55,579,000,000	$ 55,579,000,000	$ 46,655,000,000
Finance and Financial Products [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	12,736,000,000	12,736,000,000	13,129,000,000
Berkshire Hathaway Subsidiaries [Member] \| Line of Credit and Commercial Paper Facilities [Member]
Debt Instrument [Line Items]
Unused lines of credit available	7,800,000,000	7,800,000,000
Berkshire Hathaway Energy Company and Subsidiaries [Member] \| Line of Credit and Commercial Paper Facilities [Member]
Debt Instrument [Line Items]
Unused lines of credit available	4,600,000,000	4,600,000,000
Berkshire Hathaway (Parent) [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	8,354,000,000	8,354,000,000	8,311,000,000
Berkshire Hathaway (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation	3,400,000,000	3,400,000,000
Berkshire Hathaway Energy [Member] \| Senior Unsecured Notes [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	1,500,000,000
Berkshire Hathaway Energy [Member] \| Senior Unsecured Notes Due 2020 at 2.4% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	350,000,000
Debt instrument, interest rate, stated percentage	2.40%	2.40%
Berkshire Hathaway Energy [Member] \| Senior Unsecured Notes Due 2025 at 3.5% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	400,000,000
Debt instrument, interest rate, stated percentage	3.50%	3.50%
Berkshire Hathaway Energy [Member] \| Senior Unsecured Notes Due 2045 at 4.5% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	750,000,000
Debt instrument, interest rate, stated percentage	4.50%	4.50%
Berkshire Hathaway Energy Subsidiaries [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	28,439,000,000	28,439,000,000	23,033,000,000
Berkshire Hathaway Energy Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| AltaLink [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	4,000,000,000	4,000,000,000
BNSF [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	19,280,000,000	19,280,000,000	17,006,000,000
BNSF [Member] \| Debentures [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		3,000,000,000
BNSF [Member] \| Debentures Due 2024 at 3.75% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		500,000,000
Debt instrument, interest rate, stated percentage	3.75%	3.75%
BNSF [Member] \| Debentures Due 2024 at 3.4% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		700,000,000
Debt instrument, interest rate, stated percentage	3.40%	3.40%
BNSF [Member] \| Debentures Due 2044 at 4.9% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		1,000,000,000
Debt instrument, interest rate, stated percentage	4.90%	4.90%
BNSF [Member] \| Debentures Due 2044 at 4.5% [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		800,000,000
Debt instrument, interest rate, stated percentage	4.55%	4.55%
Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	11,178,000,000	11,178,000,000	11,178,000,000
Berkshire Hathaway Finance Corporation [Member] \| Senior Notes [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		1,150,000,000
Berkshire Hathaway Finance Corporation [Member] \| Senior Notes Due 2017, Floating Rate [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		1,050,000,000
Berkshire Hathaway Finance Corporation [Member] \| Senior Notes Due 2018 at 2% [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		$ 100,000,000
Debt instrument, interest rate, stated percentage	2.00%	2.00%