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

No definition available.

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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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- Details

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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

+ Details

Name:	us-gaap_DebtAndCapitalLeaseObligations
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Period Type:	instant

- Definition

Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of debt outstanding by type or by instrument at that time.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

+ 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 210.5-02.22)

-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 22

-Article 5

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section H

+ Details

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ 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.(a),16(a)(1))

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Subparagraph a(1)

-Article 7

Reference 3: 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))

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 2, 3

-Article 9

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Subparagraph a

-Article 5

Reference 6: 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)

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

+ Details

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- Definition

Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of short-term debt outstanding by type or by instrument at that time.

+ 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))

-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

-Subparagraph b

-Article 5

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Article 5

-Subsection 19, 20, 22

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-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 03

-Paragraph 16

-Article 9

+ Details

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Notes payable and other borrowings (Detail) (USD $) In Millions, unless otherwise specified					3 Months Ended			3 Months Ended			3 Months Ended					3 Months Ended			3 Months Ended					3 Months Ended			3 Months Ended
	Mar. 31, 2013 Railroad, Utilities and Energy [Member]	Dec. 31, 2012 Railroad, Utilities and Energy [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member] MidAmerican [Member]	Dec. 31, 2012 Railroad, Utilities and Energy [Member] MidAmerican [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member] MidAmerican [Member] Debt [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member] MidAmerican Subsidiaries [Member]	Dec. 31, 2012 Railroad, Utilities and Energy [Member] MidAmerican Subsidiaries [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member] MidAmerican Subsidiaries [Member] Debt [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member] BNSF [Member]	Dec. 31, 2012 Railroad, Utilities and Energy [Member] BNSF [Member]	Mar. 31, 2013 Railroad, Utilities and Energy [Member] BNSF [Member] Debt [Member]	Mar. 31, 2013 Finance and Financial Products [Member]	Dec. 31, 2012 Finance and Financial Products [Member]	Mar. 31, 2013 Finance and Financial Products [Member] Berkshire Hathaway Finance Corporation [Member]	Dec. 31, 2012 Finance and Financial Products [Member] Berkshire Hathaway Finance Corporation [Member]	Mar. 31, 2013 Finance and Financial Products [Member] Berkshire Hathaway Finance Corporation [Member] Debt [Member]	Mar. 31, 2013 Finance and Financial Products [Member] Other Finance Subsidiaries [Member]	Dec. 31, 2012 Finance and Financial Products [Member] Other Finance Subsidiaries [Member]	Mar. 31, 2013 Finance and Financial Products [Member] Other Finance Subsidiaries [Member] Debt [Member]	Mar. 31, 2013 Insurance and Other [Member]	Dec. 31, 2012 Insurance and Other [Member]	Mar. 31, 2013 Insurance and Other [Member] Berkshire Hathaway (Parent) [Member]	Dec. 31, 2012 Insurance and Other [Member] Berkshire Hathaway (Parent) [Member]	Mar. 31, 2013 Insurance and Other [Member] Berkshire Hathaway (Parent) [Member] Debt [Member]	Mar. 31, 2013 Insurance and Other [Member] Insurance and Other Subsidiaries [Member]	Dec. 31, 2012 Insurance and Other [Member] Insurance and Other Subsidiaries [Member]	Mar. 31, 2013 Insurance and Other [Member] Insurance and Other Subsidiaries [Member] Debt [Member]
Notes payable and other borrowings [Line Items]
Maturity date, range, start					2014			2013			2013					2013			2013					2013			2013
Maturity date, range, end					2037			2042			2097					2042			2036					2047			2035
Short-term debt, weighted average interest rate																									0.30%
Senior unsecured debt			$ 4,621	$ 4,621
Weighted Average Interest Rate, percentage			6.30%			5.00%			5.30%					4.00%			4.90%					2.70%			6.00%
Notes payable and other borrowings	36,890	36,156				16,318	17,002		15,951	14,533		12,960	13,045	11,194	11,186		1,766	1,859		13,399	13,535	8,309	8,323
Short-term borrowings																									1,354	1,416
Other borrowings																									$ 3,736	$ 3,796