Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of long-term debt and capital lease obligation 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 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

+ Details

Name:	us-gaap_LongTermDebtAndCapitalLeaseObligations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Notes payable and other borrowings - Narrative (Detail) € in Millions, $ in Millions	1 Months Ended
	Aug. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	May 31, 2016 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2016 EUR (€)
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings	$ 750
Insurance and Other Subsidiaries [Member] \| Precision Castparts Corp. [Member]
Debt Instrument [Line Items]
Other borrowings		$ 4,700
Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Repayments of borrowings	1,000
Debentures Due 2046 at 3.9% [Member] \| BNSF [Member] \| Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 750
Debt instrument, interest rate, stated percentage			3.90%
Senior Unsecured Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	750				€ 2,750
Senior Unsecured Notes [Member] \| Notes Due 2020 at 0.50% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| €					€ 1,000
Debt instrument, interest rate, stated percentage				0.50%	0.50%
Senior Unsecured Notes [Member] \| Notes Due 2024 at 1.30% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| €					€ 1,000
Debt instrument, interest rate, stated percentage				1.30%	1.30%
Senior Unsecured Notes [Member] \| Notes Due 2028 at 2.15% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| €					€ 750
Debt instrument, interest rate, stated percentage				2.15%	2.15%
Senior Unsecured Notes [Member] \| Notes Due 2018 at 1.15% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 500
Debt instrument, interest rate, stated percentage	1.15%
Senior Unsecured Notes [Member] \| Notes Due 2018, Floating Rate [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 250
Additional Senior Unsecured Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 5,500
Additional Senior Unsecured Notes [Member] \| Notes Due 2021 at 2.20% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 1,000
Debt instrument, interest rate, stated percentage				2.20%	2.20%
Additional Senior Unsecured Notes [Member] \| Notes Due 2023 at 2.75% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 2,000
Debt instrument, interest rate, stated percentage				2.75%	2.75%
Additional Senior Unsecured Notes [Member] \| Notes Due 2026 at 3.125% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 2,500
Debt instrument, interest rate, stated percentage				3.125%	3.125%
Senior Notes [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	1,250			$ 3,500
Senior Notes [Member] \| Notes Due 2018, Floating Rate [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				1,000
Senior Notes [Member] \| Notes Due 2018 at 1.45% [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 750
Debt instrument, interest rate, stated percentage				1.45%	1.45%
Senior Notes [Member] \| Notes Due 2019 at 1.70% [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 1,250
Debt instrument, interest rate, stated percentage				1.70%	1.70%
Senior Notes [Member] \| Notes Due 2019, Floating Rate [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	250			$ 500
Senior Notes [Member] \| Notes Due 2019 at 1.30% [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Finance and Financial Products [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,000
Debt instrument, interest rate, stated percentage	1.30%