Year the debt matures, in CCYY format.

No definition available.

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- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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- 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.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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://fasb.org/us-gaap/role/ref/legacyRef
-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

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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

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Notes payable and other borrowings (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	3 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 JPY (¥)	Mar. 31, 2020 GBP (£)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings		€ 6,850	¥ 430	£ 1,750
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 37,486				$ 37,590
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,328				8,324
Weighted average interest rate, percentage	3.20%	3.20%	3.20%	3.20%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,513				7,641
Weighted average interest rate, percentage	1.00%	1.00%	1.00%	1.00%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2021
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2035
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 3,978				3,938
Weighted average interest rate, percentage	0.50%	0.50%	0.50%	0.50%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2024
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Other borrowings	$ 5,241				5,262
Short-term borrowings	$ 1,467				1,472
Weighted average interest rate, percentage	4.10%	4.10%	4.10%	4.10%
Short-term borrowings, weighted average interest rate	3.00%	3.00%	3.00%	3.00%
Insurance and Other [Member] \| Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,828				8,679
Weighted average interest rate, percentage	4.10%	4.10%	4.10%	4.10%
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,131				2,274
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2059
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 66,747				65,778
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Senior unsecured debt	$ 11,459				8,581
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2021
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2050
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 30,035				30,772
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 2,088				3,214
Short-term borrowings, weighted average interest rate	2.40%	2.40%	2.40%	2.40%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe and subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,165				$ 23,211
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe and subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe and subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2097