Berkshire Hathaway (BRK-B) 10-Q 9 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 26, 2020
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity File Number	001-14905
Entity Tax Identification Number	47-0813844
Entity Address, Address Line One	3555 Farnam Street
Entity Address, City or Town	Omaha
Entity Address, State or Province	NE
Entity Address, Postal Zip Code	68131
City Area Code	402
Local Phone Number	346-1400
Entity Registrant Name	BERKSHIRE HATHAWAY INC
Entity Central Index Key	0001067983
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Current Reporting Status	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Interactive Data Current	Yes
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false
Common Class A [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		649,184
Security 12b Title	Class A Common Stock
Trading Symbol	BRK.A
Security Exchange Name	NYSE
Common Class B [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		1,370,951,744
Security 12b Title	Class B Common Stock
Trading Symbol	BRK.B
Security Exchange Name	NYSE
M 0.750 Senior Notes Due 2023 [Member]
Document Information [Line Items]
Security 12b Title	0.750% Senior Notes due 2023
Trading Symbol	BRK23
Security Exchange Name	NYSE
M 1.125 Senior Notes Due 2027 [Member]
Document Information [Line Items]
Security 12b Title	1.125% Senior Notes due 2027
Trading Symbol	BRK27
Security Exchange Name	NYSE
M 1.625 Senior Notes Due 2035 [Member]
Document Information [Line Items]
Security 12b Title	1.625% Senior Notes due 2035
Trading Symbol	BRK35
Security Exchange Name	NYSE
M 1.300 Senior Notes Due 2024 [Member]
Document Information [Line Items]
Security 12b Title	1.300% Senior Notes due 2024
Trading Symbol	BRK24
Security Exchange Name	NYSE
M 2.150 Senior Notes Due 2028 [Member]
Document Information [Line Items]
Security 12b Title	2.150% Senior Notes due 2028
Trading Symbol	BRK28
Security Exchange Name	NYSE
M 0.250 Senior Notes Due 2021 [Member]
Document Information [Line Items]
Security 12b Title	0.250% Senior Notes due 2021
Trading Symbol	BRK21
Security Exchange Name	NYSE
M 0.625 Senior Notes Due 2023 [Member]
Document Information [Line Items]
Security 12b Title	0.625% Senior Notes due 2023
Trading Symbol	BRK23A
Security Exchange Name	NYSE
M 0.000 Senior Notes Due 2025 [Member]
Document Information [Line Items]
Security 12b Title	0.000% Senior Notes due 2025
Trading Symbol	BRK25
Security Exchange Name	NYSE
M 2.375 Senior Notes Due 2039 [Member]
Document Information [Line Items]
Security 12b Title	2.375% Senior Notes due 2039
Trading Symbol	BRK39
Security Exchange Name	NYSE
M 2.625 Senior Notes Due 2059 [Member]
Document Information [Line Items]
Security 12b Title	2.625% Senior Notes due 2059
Trading Symbol	BRK59
Security Exchange Name	NYSE

Consolidated Balance Sheets

Consolidated Balance Sheets € in Millions, £ in Millions, $ in Millions, ¥ in Billions		Sep. 30, 2020USD ($)		Dec. 31, 2019USD ($)
ASSETS
Investments in fixed maturity securities		$ 19,435		$ 18,685
Investments in equity securities		245,317	[1]	248,027	[2]
Loans and finance receivables		18,584		17,527
Inventories		19,361		19,852
Equipment held for lease		14,714		15,065
Goodwill		71,865		81,882
Deferred charges under retroactive reinsurance contracts		13,012		13,747
Total assets		829,946		817,729
LIABILITIES
Unpaid losses and loss adjustment expenses		78,041		73,019
Unpaid losses and loss adjustment expenses under retroactive reinsurance contracts		41,786		42,441
Income taxes, principally deferred		67,340		66,799
Total liabilities		410,731		389,166
Shareholders’ equity:
Common stock		8		8
Capital in excess of par value		35,621		35,658
Accumulated other comprehensive income		(5,190)		(5,243)
Retained earnings		408,791		402,493
Treasury stock, at cost		(24,075)		(8,125)
Berkshire Hathaway shareholders’ equity		415,155		424,791
Noncontrolling interests		4,060		3,772
Total shareholders’ equity		419,215		428,563
Total liabilities and shareholders' equity		829,946		817,729
Insurance and Other [Member]
ASSETS
Cash and cash equivalents	[3]	23,078		61,151
Short-term investments in U.S. Treasury Bills		118,906		63,822
Investments in fixed maturity securities		19,435		18,685
Investments in equity securities		245,317		248,027
Equity method investments		17,152		17,505
Loans and finance receivables		18,584		17,527
Other receivables		34,389		32,418
Inventories		19,361		19,852
Property, plant and equipment		21,141		21,438
Equipment held for lease		14,714		15,065
Goodwill		47,091		57,052
Other intangible assets		29,652		31,051
Deferred charges under retroactive reinsurance contracts		13,012		13,747
Other		14,121		13,232
Total assets		635,953		630,572
LIABILITIES
Unpaid losses and loss adjustment expenses		78,041		73,019
Unpaid losses and loss adjustment expenses under retroactive reinsurance contracts		41,786		42,441
Unearned premiums		22,018		19,782
Life, annuity and health insurance benefits		20,975		20,155
Other policyholder liabilities		8,201		7,723
Accounts payable, accruals and other liabilities		28,976		27,611
Payable for purchase of U.S. Treasury Bills		6,795
Derivative contract liabilities		1,547		968
Aircraft repurchase liabilities and unearned lease revenues		5,390		5,281
Notes payable and other borrowings		38,891		37,590
Total liabilities		252,620		234,570
Railroad, Utilities and Energy [Member]
ASSETS
Cash and cash equivalents	[3]	3,739		3,024
Receivables		3,426		3,417
Property, plant and equipment		140,398		137,838
Goodwill		24,774		24,830
Regulatory assets		2,933		2,881
Other		18,723		15,167
Total assets		193,993		187,157
LIABILITIES
Accounts payable, accruals and other liabilities		15,050		14,708
Regulatory liabilities		6,921		7,311
Notes payable and other borrowings		68,800		65,778
Total liabilities		$ 90,771		$ 87,797
[1]	Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion).
[2]	Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion).
[3]	Cash and cash equivalents includes U.S. Treasury Bills with maturities of three months or less when purchased of $2.4 billion at September 30, 2020 and $37.1 billion at December 31, 2019.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Billions	Sep. 30, 2020	Dec. 31, 2019
U.S. Treasury Bills [Member]
Cash equivalents	$ 2.4	$ 37.1

Consolidated Statements of Earn

Consolidated Statements of Earnings - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues:
Sales and service revenues		$ 43,494	$ 45,169	$ 122,324	$ 132,021
Leasing revenues		1,316	1,438	3,905	4,365
Total revenues		63,024	64,972	181,129	189,248
Investment and derivative contract gains/losses		31,582	10,926	1,392	41,296
Costs and expenses:
Total costs and expenses		56,966	56,053	172,564	165,585
Earnings before income taxes and equity method earnings		37,640	19,845	9,957	64,959
Equity method earnings		290	644	333	936
Earnings before income taxes		37,930	20,489	10,290	65,895
Income tax expense		7,517	3,832	3,167	13,333
Net earnings		30,413	16,657	7,123	52,562
Earnings attributable to noncontrolling interests		276	133	437	304
Net earnings attributable to Berkshire Hathaway shareholders		$ 30,137	$ 16,524	$ 6,686	$ 52,258
Equivalent Class A [Member]
Costs and expenses:
Net earnings per average equivalent share		$ 18,994	$ 10,119	$ 4,160	$ 31,944
Average equivalent shares outstanding		1,586,698	1,633,002	1,607,041	1,635,903
Equivalent Class B [Member]
Costs and expenses:
Net earnings per average equivalent share	[1]	$ 12.66	$ 6.75	$ 2.77	$ 21.30
Average equivalent shares outstanding		2,380,046,304	2,449,502,430	2,410,561,550	2,453,854,768
Insurance and Other [Member]
Revenues:
Insurance premiums earned		$ 15,913	$ 15,323	$ 47,256	$ 44,505
Sales and service revenues		32,703	34,026	93,332	100,563
Leasing revenues		1,316	1,438	3,905	4,365
Interest, dividend and other investment income		1,717	2,483	6,143	6,895
Total revenues		51,649	53,270	150,636	156,328
Costs and expenses:
Insurance losses and loss adjustment expenses		11,667	10,858	32,712	31,701
Life, annuity and health insurance benefits		1,311	1,176	4,101	3,245
Insurance underwriting expenses		3,228	2,708	9,219	8,033
Cost of sales and services		25,957	26,950	74,565	79,764
Cost of leasing		854	1,010	2,605	3,030
Selling, general and administrative expenses		5,181	4,384	14,304	13,645
Goodwill and intangible asset impairments		25		10,659
Interest expense		263	261	817	790
Total costs and expenses		48,486	47,347	148,982	140,208
Freight Rail Transportation [Member]
Revenues:
Total revenues		5,148	5,982	15,101	17,558
Costs and expenses:
Expenses		3,161	3,839	9,625	11,706
Utilities and Energy [Member]
Revenues:
Sales and service revenues		4,451	4,338	11,504	11,729
Costs and expenses:
Cost of sales and other expenses		3,101	2,981	8,326	8,503
Railroad, Utilities and Energy [Member]
Revenues:
Service revenues and other income		1,776	1,382	3,888	3,633
Total revenues		11,375	11,702	30,493	32,920
Costs and expenses:
Other expenses		1,481	1,162	3,422	2,990
Interest expense		737	724	2,209	2,178
Total costs and expenses		$ 8,480	$ 8,706	$ 23,582	$ 25,377
[1]	Class B shares are economically equivalent to one-fifteen

Consolidated Statements of Ea_2

Consolidated Statements of Earnings (Parenthetical)	Sep. 30, 2020
Income Statement [Abstract]
Economic equivalent of Class B share to Class A share	0.0667%

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 30,413	$ 16,657	$ 7,123	$ 52,562
Other comprehensive income:
Unrealized appreciation of investments	19	(39)	42	179
Applicable income taxes	(4)	10	(13)	(40)
Foreign currency translation	791	(700)	(77)	(534)
Applicable income taxes	(3)	6	34	3
Defined benefit pension plans	(24)	(45)	86	47
Applicable income taxes	8	7	(14)	(16)
Other, net	16	10	(19)	(35)
Other comprehensive income, net	803	(751)	39	(396)
Comprehensive income	31,216	15,906	7,162	52,166
Comprehensive income attributable to noncontrolling interests	302	112	423	301
Comprehensive income attributable to Berkshire Hathaway shareholders	$ 30,914	$ 15,794	$ 6,739	$ 51,865

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Millions	Total	Cumulative effect, period of adoption, adjustment	Common stock and capital in excess of par value	Accumulated other comprehensive income	Retained earnings	Retained earningsCumulative effect, period of adoption, adjustment	Treasury Stock	Noncontrolling interests
Beginning Balance at Dec. 31, 2018	$ 352,500		$ 35,715	$ (5,015)	$ 321,112		$ (3,109)	$ 3,797
Net earnings	21,732				21,661			71
Other comprehensive income, net	310			288				22
Issuance (acquisition) of common stock	(1,677)		13				(1,690)
Transactions with noncontrolling interests	(274)		(98)					(176)
Ending Balance at Mar. 31, 2019	372,591		35,630	(4,727)	342,773		(4,799)	3,714
Beginning Balance at Dec. 31, 2018	352,500		35,715	(5,015)	321,112		(3,109)	3,797
Net earnings	52,562
Other comprehensive income, net	(396)
Ending Balance at Sep. 30, 2019	401,558		35,620	(5,408)	373,334		(5,937)	3,949
Beginning Balance at Mar. 31, 2019	372,591		35,630	(4,727)	342,773		(4,799)	3,714
Net earnings	14,173				14,073			100
Other comprehensive income, net	45			49				(4)
Issuance (acquisition) of common stock	(435)		8				(443)
Transactions with noncontrolling interests	17		(20)					37
Ending Balance at Jun. 30, 2019	386,391		35,618	(4,678)	356,846		(5,242)	3,847
Net earnings	16,657				16,524			133
Other comprehensive income, net	(751)			(730)				(21)
Issuance (acquisition) of common stock	(695)						(695)
Transactions with noncontrolling interests and other	(44)		2		(36)			(10)
Ending Balance at Sep. 30, 2019	401,558		35,620	(5,408)	373,334		(5,937)	3,949
Beginning Balance at Dec. 31, 2019	$ 428,563	$ (388)	35,666	(5,243)	402,493	$ (388)	(8,125)	3,772
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Net earnings	$ (49,697)				(49,746)			49
Other comprehensive income, net	(1,531)			(1,478)				(53)
Issuance (acquisition) of common stock	(1,575)						(1,575)
Transactions with noncontrolling interests	(137)		(39)					(98)
Ending Balance at Mar. 31, 2020	375,235		35,627	(6,721)	352,359		(9,700)	3,670
Beginning Balance at Dec. 31, 2019	428,563	$ (388)	35,666	(5,243)	402,493	$ (388)	(8,125)	3,772
Net earnings	7,123
Other comprehensive income, net	39
Ending Balance at Sep. 30, 2020	419,215		35,629	(5,190)	408,791		(24,075)	4,060
Beginning Balance at Mar. 31, 2020	375,235		35,627	(6,721)	352,359		(9,700)	3,670
Net earnings	26,407				26,295			112
Other comprehensive income, net	767			754				13
Issuance (acquisition) of common stock	(5,115)						(5,115)
Transactions with noncontrolling interests	(41)		(4)					(37)
Ending Balance at Jun. 30, 2020	397,253		35,623	(5,967)	378,654		(14,815)	3,758
Net earnings	30,413				30,137			276
Other comprehensive income, net	803			777				26
Issuance (acquisition) of common stock	(9,260)						(9,260)
Transactions with noncontrolling interests	6		6
Ending Balance at Sep. 30, 2020	$ 419,215		$ 35,629	$ (5,190)	$ 408,791		$ (24,075)	$ 4,060

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020		Sep. 30, 2019
Cash flows from operating activities:
Net earnings	$ 7,123		$ 52,562
Adjustments to reconcile net earnings to operating cash flows:
Investment (gains) losses	(2,032)		(40,079)
Depreciation and amortization	7,692		7,407
Other, including asset impairment charges	10,934		(1,740)
Changes in operating assets and liabilities:
Losses and loss adjustment expenses	4,480		3,252
Deferred charges reinsurance assumed	735		745
Unearned premiums	2,544		2,663
Receivables and originated loans	(3,223)		(3,618)
Other assets	(1,673)		(2,419)
Other liabilities	2,446		(889)
Income taxes	201		8,726
Net cash flows from operating activities	29,227		26,610
Cash flows from investing activities:
Purchases of equity securities	(22,406)		(15,090)
Sales of equity securities	28,564		7,127
Purchases of U.S. Treasury Bills and fixed maturity securities	(153,897)		(72,189)
Sales of U.S. Treasury Bills and fixed maturity securities	23,744		13,602
Redemptions and maturities of U.S. Treasury Bills and fixed maturity securities	81,252		94,742
Purchases of loans and finance receivables	(619)		(57)
Collections of loans and finance receivables	268		259
Acquisitions of businesses, net of cash acquired	(111)		(732)
Purchases of property, plant and equipment and equipment held for lease	(9,516)		(11,139)
Other	(1,685)		(1,067)
Net cash flows from investing activities	(54,406)		15,456
Cash flows from financing activities:
Changes in short term borrowings, net	(1,062)		165
Acquisition of treasury stock	(15,712)		(2,807)
Other	(196)		(341)
Net cash flows from financing activities	(11,676)		2,509
Effects of foreign currency exchange rate changes	(340)		(95)
Increase (decrease) in cash and cash equivalents and restricted cash	(37,195)		44,480
Cash and cash equivalents and restricted cash at beginning of year	64,632		30,811
Cash and cash equivalents and restricted cash at end of third quarter *	27,437		75,291
Restricted cash, included in other assets at beginning of year	457		450
Restricted cash, included in other assets at end of third quarter	$ 620		$ 515
Restricted Cash and Cash Equivalents, Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsMember		us-gaap:OtherAssetsMember
Insurance and Other [Member]
Cash flows from financing activities:
Proceeds from borrowings	$ 3,435		$ 8,141
Repayments of borrowings	(2,116)		(5,046)
Cash and cash equivalents at beginning of year	61,151	[1]	27,749
Cash and cash equivalents at end of third quarter	23,078	[1]	71,064
Railroad, Utilities and Energy [Member]
Cash flows from financing activities:
Proceeds from borrowings	6,424		4,163
Repayments of borrowings	(2,449)		(1,766)
Cash and cash equivalents at beginning of year	3,024	[1]	2,612
Cash and cash equivalents at end of third quarter	$ 3,739	[1]	$ 3,712
[1]	Cash and cash equivalents includes U.S. Treasury Bills with maturities of three months or less when purchased of $2.4 billion at September 30, 2020 and $37.1 billion at December 31, 2019.

General

General	9 Months Ended
	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
General	Note 1. General The accompanying unaudited Consolidated Financial Statements include the accounts of Berkshire Hathaway Inc. (“Berkshire” or “Company”) consolidated with the accounts of all its subsidiaries and affiliates in which Berkshire holds controlling financial interests as of the financial statement date. In these notes, the terms “us,” “we” or “our” refer to Berkshire and its consolidated subsidiaries. Reference is made to Berkshire’s most recently issued Annual Report on Form 10-K (“Annual Report”), which includes information necessary or useful to understanding Berkshire’s businesses and financial statement presentations. Our significant accounting policies and practices were presented as Note 1 to the Consolidated Financial Statements included in the Annual Report. Changes to those policies due to the adoption of new accounting standards are described in Note 2. Financial information in this Quarterly Report reflects all adjustments (consisting only of normal recurring adjustments) that are, in the opinion of management, necessary to a fair statement of results for the interim periods in accordance with accounting principles generally accepted in the United States (“GAAP”). For a number of reasons, our results for interim periods are not normally indicative of results to be expected for the year. The timing and magnitude of catastrophe losses incurred by insurance subsidiaries and the estimation error inherent to the process of determining liabilities for unpaid losses of insurance subsidiaries can be more significant to results of interim periods than to results for a full year. Given the size of our equity security investment portfolio, changes in market prices and the related changes in unrealized gains on equity securities will produce significant volatility in our interim and annual earnings. In addition, changes in the fair values of certain derivative contract liabilities, gains and losses from the periodic revaluation of certain assets and liabilities denominated in foreign currencies and the magnitude of asset impairment charges can cause significant variations in periodic net earnings. The novel coronavirus (“COVID-19”) spread rapidly across the world in 2020 and was declared a pandemic by the World Health Organization. The government and private sector responses to contain its spread began to significantly affect our operating businesses in March. COVID-19 has since adversely affected nearly all of our operations, although the effects are varying significantly. The duration and extent of the effects over longer terms cannot be reasonably estimated at this time. The risks and uncertainties resulting from the pandemic that may affect our future earnings, cash flows and financial condition include the time necessary to develop and produce a safe and effective vaccine that can be widely distributed throughout the world and the long-term effect on the demand for certain of our products and services. Accordingly, significant estimates used in the preparation of our financial statements including those associated with evaluations of certain long-lived assets, goodwill and other intangible assets for impairment, expected credit losses on amounts owed to us and the estimations of certain losses assumed under insurance and reinsurance contracts may be subject to significant adjustments in future periods. Additionally, GEICO’s underwriting results will likely be negatively affected over the remainder of the year and in the first quarter of 2021, as the remaining impact of the GEICO Giveback program (a program whereby all voluntary auto and motorcycle insurance policies renewed and newly issued during the period between April 8, 2020 and October 7, 2020 receive a 15% premium rate reduction) will be reflected in earned premiums during these periods.

New accounting pronouncements

New accounting pronouncements	9 Months Ended
	Sep. 30, 2020
Accounting Changes And Error Corrections [Abstract]
New accounting pronouncements	Note 2. New accounting pronouncements We adopted Accounting Standards Codification (“ASC”) 326 “Financial Instruments-Credit Losses” on January 1, 2020. ASC 326 provides for the measurement of expected credit losses on financial assets that are carried at amortized cost based on the net amounts expected to be collected. Measurements of expected credit losses therefore include provisions for non-collection, whether the risk is probable or remote. Prior to the adoption of ASC 326, credit losses were measured when non-collection was considered probable based on the prevailing facts and circumstances. We elected to not measure an allowance for expected credit losses on accrued interest and instead reverse uncollectible accrued interest through interest income on a timely basis. Upon adoption of ASC 326, we recorded a charge to retained earnings of $388 million representing the cumulative after-tax increase in our allowances for credit losses, which was primarily related to our manufactured housing loans. Expected credit losses for such financial assets are based on the net present value of future principal payments less estimated expenses related to the charge-off and foreclosure of expected uncollectible loans and include provisions for loans that are not in foreclosure. Our principal credit quality indicator is whether the loans are performing. Expected credit loss estimates consider historical default rates, collateral recovery rates, historical runoff rates, interest rates, reductions of future cash flows for modified loans, the historical time elapsed from last payment until foreclosure, among other matters. In addition, our estimates consider current conditions and reasonable and supportable forecasts. Notes to Consolidated Financial Statements (Continued) Note 2. New accounting pronouncements (Continued) Trade receivables, insurance premium receivables and other receivables are primarily short-term in duration with stated collection terms of less than one year from the date of origination. In establishing credit loss allowances for such receivables, we primarily utilize credit loss history. However, credit loss allowances may be adjusted as a result of current conditions and when we expect reasonable and supportable forecasts to deviate from historical experience. In evaluating expected credit losses of reinsurance recoverables, we review the credit quality of the counterparty and consider credit ratings, right-of-offset provisions within reinsurance contracts and other forms of credit enhancement including, collateral, funds held arrangements, guarantees, as well as other publicly available information. We adopted ASU 2017-04 “Simplifying the Test for Goodwill Impairment” as of January 1, 2020. Under ASU 2017-04, the measurement of a goodwill impairment is represented by the excess of the carrying value over the fair value of the reporting unit and is limited to the carrying value of goodwill. In August 2018, the FASB issued ASU 2018-12 “Targeted Improvements to the Accounting for Long-Duration Contracts.” ASU 2018-12 requires periodic reassessment of actuarial and discount rate assumptions used to value policyholder liabilities and deferred acquisition costs arising from long-duration insurance and reinsurance contracts, with the effects of changes in cash flow assumptions reflected in earnings and the effects of changes in discount rate assumptions reflected in other comprehensive income. Currently, the actuarial and discount rate assumptions are set at the contract inception date and not subsequently changed, except under limited circumstances. ASU 2018-12 requires new disclosures and is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. We are evaluating the effect this standard will have on our Consolidated Financial Statements.

Investments in fixed maturity s

Investments in fixed maturity securities	9 Months Ended
	Sep. 30, 2020
Investments Debt And Equity Securities [Abstract]
Investments in fixed maturity securities	Note 3. Investments in fixed maturity securities Investments in fixed maturity securities as of September 30, 2020 and December 31, 2019 are summarized by type below (in millions). Amortized Cost Unrealized Gains Unrealized Losses Fair Value September 30, 2020 U.S. Treasury, U.S. government corporations and agencies $ 3,311 $ 66 $ — $ 3,377 Foreign governments 9,898 82 (11 ) 9,969 Corporate bonds 5,125 455 (6 ) 5,574 Other 447 70 (2 ) 515 $ 18,781 $ 673 $ (19 ) $ 19,435 December 31, 2019 U.S. Treasury, U.S. government corporations and agencies $ 3,054 $ 37 $ (1 ) $ 3,090 Foreign governments 8,584 63 (9 ) 8,638 Corporate bonds 5,896 459 (3 ) 6,352 Other 539 67 (1 ) 605 $ 18,073 $ 626 $ (14 ) $ 18,685 Investments in foreign governments include securities issued by national and provincial government entities as well as instruments that are unconditionally guaranteed by such entities. As of September 30, 2020, approximately 87% of our foreign government holdings were rated AA or higher by at least one of the major rating agencies. The amortized cost and estimated fair value of fixed maturity securities as of September 30, 2020 are summarized below by contractual maturity dates (in millions). Actual maturities may differ from contractual maturities due to early call or prepayment rights held by issuers. Due in one year or less Due after one year through five years Due after five years through ten years Due after ten years Mortgage- backed securities Total Amortized cost $ 9,847 $ 7,885 $ 302 $ 405 $ 342 $ 18,781 Fair value 9,887 8,030 349 764 405 19,435

Investments in equity securitie

Investments in equity securities	9 Months Ended
	Sep. 30, 2020
Investments Debt And Equity Securities [Abstract]
Investments in equity securities	Notes to Consolidated Financial Statements (Continued) Note 4. Investments in equity securities Investments in equity securities as of September 30, 2020 and December 31, 2019 are summarized in the tables below (in millions). Cost Basis Net Unrealized Gains Fair Value September 30, 2020* Banks, insurance and finance $ 27,145 $ 29,065 $ 56,210 Consumer products 37,016 98,022 135,038 Commercial, industrial and other 41,468 12,601 54,069 $ 105,629 $ 139,688 $ 245,317 * Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion). Cost Basis Net Unrealized Gains Fair Value December 31, 2019* Banks, insurance and finance $ 40,419 $ 61,976 $ 102,395 Consumer products 38,887 60,747 99,634 Commercial, industrial and other 31,034 14,964 45,998 $ 110,340 $ 137,687 $ 248,027 * Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion). On August 8, 2019, Berkshire invested a total of $10 billion in Occidental Corporation (“Occidental”) newly issued Occidental Cumulative Perpetual Preferred Stock with an aggregate liquidation value of $10 billion, and warrants to purchase up to 80 million shares of Occidental common stock at an exercise price of $62.50 per share. In accordance with the terms of the warrants, on August 3, 2020, the number of shares of common stock that can be purchased was increased to 83.86 million shares and the exercise price was reduced to $59.62 per share. The preferred stock accrues dividends at 8% per annum and is redeemable at the option of Occidental commencing in 2029 at a redemption price equal to 105% of the liquidation preference plus any accumulated and unpaid dividends, or mandatorily under certain specified capital return events. Dividends on the preferred stock may be paid in cash or, at Occidental’s option, in shares of Occidental common stock. The warrants are exercisable in whole or in part until one year after the redemption of the preferred stock. Our investments in Occidental are included in the commercial, industrial and other category in the preceding tables.

Equity method investments

Equity method investments	9 Months Ended
	Sep. 30, 2020
Equity Method Investments And Joint Ventures [Abstract]
Equity method investments	Note 5. Equity method investments Berkshire and its subsidiaries hold investments in certain businesses that are accounted for pursuant to the equity method. Currently, the most significant of these is our investment in the common stock of The Kraft Heinz Company (“Kraft Heinz”). Kraft Heinz is one of the world’s largest manufacturers and marketers of food and beverage products, including condiments and sauces, cheese and dairy, meals, meats, refreshment beverages, coffee and other grocery products. Berkshire currently owns 325,442,152 shares of Kraft Heinz common stock representing 26.6% of the outstanding shares. Shares of Kraft Heinz common stock are publicly-traded and the fair value of our investment was approximately $9.7 billion at September 30, 2020 and $10.5 billion at December 31, 2019. The carrying value of our investment was approximately $13.1 billion at September 30, 2020 and $13.8 billion at December 31, 2019. Notes to Consolidated Financial Statements (Continued) Note 5. Equity method investments (Continued) Berkshire’s equity method earnings from Kraft Heinz were $159 million in the third quarter of 2020. Equity method losses from Kraft Heinz were $180 million in the first nine months of 2020, which included approximately $850 million for our proportionate share of goodwill and identifiable intangible asset impairment charges recorded by Kraft Heinz. As previously disclosed in Berkshire’s Form 10-Q for the third quarter of 2019, Kraft Heinz’s financial statements for the first and second quarters of 2019 were not available until August 13, 2019 when Kraft Heinz filed financial statements for those periods with the Securities and Exchange Commission. Thus, Berkshire did not record equity method earnings attributable to Kraft Heinz for each of those periods until the third quarter of 2019. Berkshire’s equity method earnings in the third quarter and first nine months of 2019 included $467 million with respect to Kraft Heinz’s results for the first nine months of 2019, of which $228 million was attributable to Kraft Heinz’s results for the first six months of 2019. Berkshire’s equity method share of the Kraft Heinz goodwill and identifiable intangible asset impairment charges for the first nine months of 2019 was $293 million. We received dividends on the common stock of $391 million in each of the first nine months of 2020 and 2019, which were recorded as reductions to the carrying value of our investment. As of September 30, 2020, the carrying value of our investment in Kraft Heinz exceeded the fair value based on the quoted market price by $3.4 billion (26% of carrying value). In light of that fact, we evaluated our investment in Kraft Heinz for impairment. We utilize no bright-line tests in such evaluations. Based on the available facts and information regarding the operating results of Kraft Heinz, our ability and intent to hold the investment until recovery, the relative amount of the decline, and the length of time that fair value was less than carrying value, we concluded that recognition of an impairment loss in earnings was not required. However, we will continue to monitor this investment and it is possible that an impairment loss will be recorded in earnings in future periods based on changes in facts and circumstances or intentions. Summarized consolidated financial information of Kraft Heinz follows (in millions). September 26, 2020 December 28, 2019 Assets $ 98,122 $ 101,450 Liabilities 48,783 49,701 Third Quarter First Nine Months 2020 2019 2020 2019 Sales $ 6,441 $ 6,076 $ 19,246 $ 18,441 Net earnings (loss) attributable to Kraft Heinz common shareholders* 597 899 (676 ) 1,753 * Other investments accounted for pursuant to the equity method include our investments in Berkadia Commercial Mortgage LLC (“Berkadia”), Pilot Travel Centers LLC (“Pilot”) and Electric Transmission Texas, LLC (“ETT”). The carrying value of our investments in these entities was approximately $4.1 billion as of September 30, 2020 and $3.7 billion as of December 31, 2019. Our equity method earnings from these entities in the first nine months were $513 million in 2020 and $491 million in 2019. Additional information concerning these investments follows. We own a 50% interest in Berkadia, with Jefferies Financial Group Inc. (“Jefferies”) owning the other 50% interest. Berkadia is a servicer of commercial real estate loans in the U.S., performing primary, master and special servicing functions for U.S. government agency programs, commercial mortgage-backed securities transactions, banks, insurance companies and other financial institutions. A source of funding for Berkadia’s operations is through its issuance of commercial paper, which is currently limited to $1.5 billion. On September 30, 2020, Berkadia’s commercial paper outstanding was $1.47 billion. The commercial paper is supported by a surety policy issued by a Berkshire insurance subsidiary. Jefferies is obligated to indemnify us for one-half of any losses incurred under the policy. A Berkshire Hathaway Energy Company subsidiary owns a 50% interest in ETT, an owner and operator of electric transmission assets in the Electric Reliability Council of Texas footprint. American Electric Power owns the other 50% interest. In 2017, we acquired a 38.6% interest in Pilot, headquartered in Knoxville, Tennessee. Pilot is the largest operator of travel centers in North America, supplying more than 11 billion gallons of fuel per year via more than 950 retail locations across 44 U.S. states and six Canadian provinces and through wholesale distribution. The Haslam family currently owns a 50.1% interest in Pilot and a third party owns the remaining 11.3% interest. We also entered into an agreement to acquire an additional 41.4% interest in Pilot in 2023, with the Haslam family retaining a 20% interest. As a result, Berkshire will become the majority owner of Pilot in 2023.

Investment gains_losses

Investment gains/losses	9 Months Ended
	Sep. 30, 2020
Investments Debt And Equity Securities [Abstract]
Investment gains/losses	Note 6. Investment gains/losses Investment gains/losses in the third quarter and first nine months of 2020 and 2019 are summarized as follows (in millions). Third Quarter First Nine Months 2020 2019 2020 2019 Equity securities: Unrealized investment gains during the period on securities held at the end of the period $ 30,837 $ 10,489 $ 16,458 $ 39,546 Investment gains/losses on securities sold during the period 1,330 135 (13,901 ) 464 32,167 10,624 2,557 40,010 Fixed maturity securities: Gross realized gains 12 59 53 71 Gross realized losses (2 ) (2 ) (22 ) (18 ) Other (552 ) 11 (556 ) 16 $ 31,625 $ 10,692 $ 2,032 $ 40,079 Equity securities gains and losses include unrealized gains and losses from changes in fair values during the period on equity securities we still own, as well as gains and losses on securities we sold during the period. As reflected in the Consolidated Statements of Cash Flows, we received proceeds from sales of equity securities of approximately $28.6 billion in the first nine months of 2020 and $7.1 billion in the first nine months of 2019. In the preceding table, investment gains/losses on equity securities sold during the period reflect the difference between the sales proceeds and the fair value of the equity securities sold at the beginning of the applicable quarterly or annual period or, if later, the purchase date. Our taxable gains/losses on equity securities sold are generally the difference between the proceeds from sales and original cost. Taxable gains were $3.9 billion in the third quarter and $666 million in first nine months of 2020. Taxable gains were $609 million in the third quarter and $1.96 billion in first nine months of 2019.

Loans and finance receivables

Loans and finance receivables	9 Months Ended
	Sep. 30, 2020
Receivables [Abstract]
Loans and finance receivables	Note 7. Loans and finance receivables Loans and finance receivables are summarized as follows (in millions). September 30, 2020 December 31, 2019 Loans and finance receivables before allowances and discounts $ 19,832 $ 18,199 Allowances for credit losses (731 ) (167 ) Unamortized acquisition discounts and points (517 ) (505 ) $ 18,584 $ 17,527 Loans and finance receivables are principally installment loans originated or acquired by our manufactured housing business. Reconciliations of the allowance for credit losses on loans and finance receivables for each of the first nine months of 2020 and 2019 follow (in millions). 2020 2019 Balance at beginning of year $ 167 $ 177 Adoption of ASC 326 486 — Provision for credit losses 177 109 Charge-offs, net of recoveries (99 ) (103 ) Balance at September 30 $ 731 $ 183 Notes to Consolidated Financial Statements (Continued) Note 7. Loans and finance receivables (Continued) As of September 30, 2020, approximately 99% of manufactured housing loan balances were evaluated collectively for impairment. As of September 30, 2020, we considered approximately 97% of the loan balances to be current as to payment status. A summary of performing and non-performing manufactured housing loans before discounts and allowances by year of loan origination as of September 30, 2020 follows (in millions). Loans and Financing Receivables by Origination Year 2020 2019 2018 2017 2016 Prior Total Performing $ 3,328 $ 2,603 $ 1,983 $ 1,471 $ 1,314 $ 6,918 $ 17,617 Non-performing 3 4 6 7 8 49 77 Total $ 3,331 $ 2,607 $ 1,989 $ 1,478 $ 1,322 $ 6,967 $ 17,694 We are party to an agreement with Seritage Growth Properties to provide a $2.0 billion term loan facility, which expires on July 31, 2023. The outstanding loan under the facility was approximately $1.6 billion at September 30, 2020 and December 31, 2019, and is secured by mortgages on real estate properties. In the first quarter of 2020, we provided a loan to Lee Enterprises, Inc. in connection with its acquisition of our newspaper operations and the repayment of its then outstanding credit facilities. The loan balance at September 30, 2020 was $538 million. We are the sole lender to each of these entities and each of these loans is current as to payment status.

Other receivables

Other receivables	9 Months Ended
	Sep. 30, 2020
Receivables [Abstract]
Other receivables	Note 8. Other receivables Other receivables of insurance and other businesses are comprised of the following (in millions). September 30, 2020 December 31, 2019 Insurance premiums receivable $ 15,379 $ 13,379 Reinsurance recoverable on unpaid losses 2,857 2,855 Trade receivables 11,840 12,275 Other 4,916 4,327 Allowances for credit losses (603 ) (418 ) $ 34,389 $ 32,418 Receivables of railroad and utilities and energy businesses are comprised of the following (in millions). September 30, 2020 December 31, 2019 Trade receivables $ 3,245 $ 3,120 Other 305 388 Allowances for credit losses (124 ) (91 ) $ 3,426 $ 3,417 Provisions for credit losses on receivables summarized in the preceding tables were $449 million in the first nine months of 2020.

Inventories

Inventories	9 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
Inventories	Note 9. Inventories Inventories are comprised of the following (in millions). September 30, 2020 December 31, 2019 Raw materials $ 4,705 $ 4,492 Work in process and other 2,712 2,700 Finished manufactured goods 4,645 4,821 Goods acquired for resale 7,299 7,839 $ 19,361 $ 19,852

Property, plant and equipment i

Property, plant and equipment including equipment held for lease	9 Months Ended
	Sep. 30, 2020
Property, plant and equipment including equipment held for lease	Note 10. Property, plant and equipment A summary of property, plant and equipment of our insurance and other businesses follows (in millions). September 30, 2020 December 31, 2019 Land, buildings and improvements $ 13,555 $ 13,259 Machinery and equipment 24,765 24,285 Furniture, fixtures and other 4,689 4,666 43,009 42,210 Accumulated depreciation (21,868 ) (20,772 ) $ 21,141 $ 21,438 A summary of property, plant and equipment of railroad and utilities and energy businesses follows (in millions). The utility generation, transmission and distribution systems and interstate natural gas pipeline assets are owned by regulated public utility and natural gas pipeline subsidiaries. September 30, 2020 December 31, 2019 Railroad: Land, track structure and other roadway $ 63,318 $ 62,404 Locomotives, freight cars and other equipment 13,477 13,482 Construction in progress 1,075 748 77,870 76,634 Accumulated depreciation (12,724 ) (12,101 ) 65,146 64,533 Utilities and energy: Utility generation, transmission and distribution systems 82,743 81,127 Interstate natural gas pipeline assets 8,281 8,165 Independent power plants and other assets 8,952 8,817 Construction in progress 5,132 3,732 105,108 101,841 Accumulated depreciation (29,856 ) (28,536 ) 75,252 73,305 $ 140,398 $ 137,838 Depreciation expense for the first nine months of 2020 and 2019 is summarized below (in millions). First Nine Months 2020 2019 Insurance and other $ 1,725 $ 1,660 Railroad, utilities and energy 4,105 3,881 $ 5,830 $ 5,541
Equipment held for lease [Member]
Property, plant and equipment including equipment held for lease	Notes to Consolidated Financial Statements (Continued) Note 11. Equipment held for lease Equipment held for lease includes railcars, aircraft, over-the-road trailers, intermodal tank containers, cranes, storage units and furniture. A summary of equipment held for lease follows (in millions). September 30, 2020 December 31, 2019 Railcars $ 9,396 $ 9,260 Aircraft 8,061 8,093 Other 4,887 4,862 22,344 22,215 Accumulated depreciation (7,630 ) (7,150 ) $ 14,714 $ 15,065 Depreciation expense for equipment held for lease in the first nine months was $900 million in 2020 and $880 million in 2019. Operating lease revenues by type for the third quarter and first nine months of 2020 and 2019 were as follows (in millions). Third Quarter First Nine Months 2020 2019 2020 2019 Fixed lease revenue $ 1,047 $ 1,097 $ 3,205 $ 3,289 Variable lease revenue 269 341 700 1,076 $ 1,316 $ 1,438 $ 3,905 $ 4,365

Goodwill and other intangible a

Goodwill and other intangible assets	9 Months Ended
	Sep. 30, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and other intangible assets	Note 12. Goodwill and other intangible assets Reconciliations of the changes in the carrying value of goodwill for the first nine months of 2020 and for the year ended December 31, 2019 follow (in millions). September 30, 2020 December 31, 2019 Balance at beginning of year $ 81,882 $ 81,025 Acquisitions of businesses 25 890 Impairment charges (10,021 ) — Other, including foreign currency translation (21 ) (33 ) Balance at end of period $ 71,865 $ 81,882 Other intangible assets and related accumulated amortization are summarized as follows (in millions). September 30, 2020 December 31, 2019 Gross carrying amount Accumulated amortization Gross carrying amount Accumulated amortization Insurance and other: Customer relationships $ 27,344 $ 5,548 $ 27,943 $ 5,025 Trademarks and trade names 5,193 774 5,286 759 Patents and technology 4,720 3,255 4,560 3,032 Other 3,319 1,347 3,364 1,286 $ 40,576 $ 10,924 $ 41,153 $ 10,102 Railroad, utilities and energy: Customer relationships $ 678 $ 352 $ 678 $ 324 Trademarks, trade names and other 325 91 325 84 $ 1,003 $ 443 $ 1,003 $ 408 Notes to Consolidated Financial Statements (Continued) Note 12. Goodwill and other intangible assets (Continued) Intangible asset amortization expense in the first nine months was $962 million in 2020 and $986 million in 2019. Intangible assets with indefinite lives were $18.3 billion as of September 30, 2020 and $19.0 billion as of December 31, 2019 and primarily related to certain customer relationships and trademarks and trade names. During the second quarter of 2020, we concluded it was necessary to reevaluate goodwill and indefinite-lived intangible assets of certain of our reporting units for impairment due to the disruptions arising from the COVID-19 pandemic. We believed that the most significant of these disruptions related to the air travel and commercial aerospace and supporting industries. We recorded pre-tax goodwill impairment charges of approximately $10 billion and pre-tax indefinite-lived intangible asset impairment charges of $638 million in the second quarter of 2020. Approximately $10 billion of these charges related to Precision Castparts Corp. (“PCC”), the largest business within Berkshire's manufacturing segment. The carrying value of PCC-related goodwill and indefinite-lived intangible assets prior to the impairment charges was approximately $31 billion. The amounts of the impairment charges were determined based on discounted cash flow methods and reflect our current assessments of the risks and uncertainties associated with the aerospace industry. Significant judgment is required in estimating the fair value of a reporting unit and in performing impairment tests. Due to the inherent uncertainty in forecasting cash flows and earnings, actual results in the future may vary significantly from the forecasts. Disruptions arising from the COVID-19 pandemic will likely continue to evolve and the effects on our businesses may differ from what we currently estimate. If the effects prove to be worse than is reflected in our current estimates, additional goodwill or indefinite-lived intangible asset impairment charges could be required.

Derivative contracts

Derivative contracts	9 Months Ended
	Sep. 30, 2020
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative contracts	Note 13. Derivative contracts We are party to derivative contracts through certain of our subsidiaries. The most significant derivative contracts consist of equity index put option contracts. The liabilities and related notional values of these contracts follow (in millions). Liabilities Notional Value September 30, 2020 $ 1,547 $ 12,472 December 31, 2019 968 14,385 The equity index put option contracts are European style options written prior to March 2008 on four major equity indexes. Notional value in the preceding table represents the aggregate undiscounted amounts payable assuming the value of each index is zero at each contract’s expiration date. Certain contracts are denominated in foreign currencies and the related notional amounts are based on the foreign currency exchange rates as of the balance sheet date. These contracts produced pre-tax losses of $43 million in the third quarter and $640 million in the first nine months of 2020 and pre-tax gains of $234 million in the third quarter and $1,217 million in the first nine months of 2019. Substantially all open contracts as of September 30, 2020 will expire by February 2023. The weighted average life of unexpired contracts at September 30, 2020 was approximately 1.25 years. Future payments, if any, under any given contract will be required if the prevailing index value is below the contract strike price at the contract expiration date. We received aggregate premiums of $2.1 billion on the contract inception dates with respect to unexpired contracts as of September 30, 2020 and we have no counterparty credit risk. The aggregate intrinsic value (the undiscounted liability assuming the contracts are settled based on the index values and foreign currency exchange rates as of the balance sheet date) was $1.2 billion at September 30, 2020 and $397 million at December 31, 2019. These contracts may not be unilaterally terminated or fully settled before the contract expiration dates and the ultimate amount of cash basis gains or losses will not be determined until the contract expiration dates. Our regulated utility subsidiaries are exposed to variations in the prices of fuel required to generate electricity, wholesale electricity purchased and sold and natural gas supplied for customers. We may use forward purchases and sales, futures, swaps and options to manage a portion of these price risks. Most of the net derivative contract assets or liabilities of our regulated utilities are probable of recovery through rates and are offset by regulatory liabilities or assets.

Unpaid losses and loss adjustme

Unpaid losses and loss adjustment expenses	9 Months Ended
	Sep. 30, 2020
Insurance [Abstract]
Unpaid losses and loss adjustment expenses	Notes to Consolidated Financial Statements (Continued) Note 14. Unpaid losses and loss adjustment expenses Our liabilities for unpaid losses and loss adjustment expenses (also referred to as “claim liabilities”) under property and casualty insurance and reinsurance contracts are based upon estimates of the ultimate claim costs associated with claim occurrences as of the balance sheet date and include estimates for incurred-but-not-reported (“IBNR”) claims. A reconciliation of the changes in claim liabilities, excluding liabilities under retroactive reinsurance contracts (see Note 15), for each of the nine months ending September 30, 2020 and 2019 follows (in millions). 2020 2019 Balances at beginning of year: Gross liabilities $ 73,019 $ 68,458 Reinsurance recoverable on unpaid losses (2,855 ) (3,060 ) Net liabilities 70,164 65,398 Incurred losses and loss adjustment expenses: Current accident year events 31,777 31,179 Prior accident years’ events 69 (396 ) Total 31,846 30,783 Paid losses and loss adjustment expenses: Current accident year events (11,691 ) (13,144 ) Prior accident years’ events (15,259 ) (13,967 ) Total (26,950 ) (27,111 ) Foreign currency translation adjustment 124 (178 ) Balances at September 30: Net liabilities 75,184 68,892 Reinsurance recoverable on unpaid losses 2,857 3,105 Gross liabilities $ 78,041 $ 71,997 Incurred losses and loss adjustment expenses shown in the preceding table were recorded in earnings and related to insured events occurring in the current year (“current accident year”) and events occurring in all prior years (“prior accident years”). We recorded a net increase in estimated ultimate liabilities for prior accident years of $69 million in the first nine months of 2020 and a net decrease of $396 million in the first nine months of 2019, which produced a corresponding increase and decrease in incurred losses and loss adjustment expenses. These changes in the ultimate liability estimates as percentages of the net liabilities at the beginning of each year were relatively insignificant. In the first nine months of 2020, we reduced estimated ultimate liabilities for prior years’ loss events for primary insurance by $273 million and increased estimates for reinsurance liabilities by $342 million. The net decrease for primary insurance was primarily attributable to lower than anticipated private passenger automobile, medical professional liability and workers’ compensation claims. The net increase related to reinsurance included increased claims estimates for legacy casualty exposures. In the first nine months of 2019, the net decrease in estimated ultimate liabilities for prior accident years was primarily attributable to private passenger automobile, medical professional liability and workers’ compensation claims, partly offset by increased liabilities for legacy casualty exposures and other commercial insurance business.

Retroactive reinsurance contrac

Retroactive reinsurance contracts	9 Months Ended
	Sep. 30, 2020
Insurance [Abstract]
Retroactive reinsurance contracts	Notes to Consolidated Financial Statements (Continued) Note 15. Retroactive reinsurance contracts Retroactive reinsurance policies provide indemnification of losses and loss adjustment expenses of short-duration insurance contracts with respect to underlying loss events that occurred prior to the contract inception date. Claims payments may commence immediately after the contract inception date or, when applicable, once a contractual retention amount has been reached. Reconciliations of the changes in estimated liabilities for retroactive reinsurance unpaid losses and loss adjustment expenses (“claim liabilities”) and related deferred charge reinsurance assumed assets for each of the nine months ending September 30, 2020 and 2019 follow (in millions). 2020 2019 Unpaid losses and loss adjustment expenses Deferred charges reinsurance assumed Unpaid losses and loss adjustment expenses Deferred charges reinsurance assumed Balances at beginning of year $ 42,441 $ (13,747 ) $ 41,834 $ (14,104 ) Incurred losses and loss adjustment expenses: Current year contracts — — 175 (82 ) Prior years’ contracts 131 735 (2 ) 827 Total 131 735 173 745 Paid losses and loss adjustment expenses (786 ) — (643 ) — Balances at September 30 $ 41,786 $ (13,012 ) $ 41,364 $ (13,359 ) Incurred losses and loss adjustment expenses, net of deferred charges $ 866 $ 918 In the preceding table, classifications of incurred losses and loss adjustment expenses are based on the inception dates of the contracts. Incurred losses and loss adjustment expenses in the first nine months related to contracts written in prior years were $866 million in 2020 and $825 million in 2019. Such losses reflected the recurring amortization of deferred charges and the effects of changes in the estimated timing and amount of future loss payments. Berkshire’s subsidiary, National Indemnity Company (“NICO”), is party to a contract with various subsidiaries of American International Group, Inc. (collectively, “AIG”), in which NICO’s ultimate liability is contractually limited to $20 billion. Our estimated ultimate claim liabilities with respect to the AIG contract at both September 30, 2020 and December 31, 2019 were $18.2 billion. Deferred charge assets related to the AIG contract were approximately $5.8 billion at September 30, 2020 and $6.3 billion at December 31, 2019.

Notes payable and other borrowi

Notes payable and other borrowings	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Notes payable and other borrowings	Note 16. Notes payable and other borrowings Notes payable and other borrowings are summarized below (dollars in millions). The weighted average interest rates and maturity date ranges shown in the following tables are based on borrowings as of September 30, 2020. Weighted Average Interest Rate September 30, 2020 December 31, 2019 Insurance and other: Berkshire Hathaway Inc. (“Berkshire”): U.S. Dollar denominated due 2020-2047 3.2 % $ 8,320 $ 8,324 Euro denominated due 2021-2035 1.0 % 7,986 7,641 Japanese Yen denominated due 2023-2060 0.6 % 5,902 3,938 Berkshire Hathaway Finance Corporation (“BHFC”): U.S. Dollar denominated due 2020-2049 4.1 % 8,829 8,679 Great Britain Pound denominated due 2039-2059 2.5 % 2,218 2,274 Other subsidiary borrowings due 2020-2045 4.2 % 4,676 5,262 Subsidiary short-term borrowings 2.7 % 960 1,472 $ 38,891 $ 37,590 Notes to Consolidated Financial Statements (Continued) Note 16. Notes payable and other borrowings (Continued) In March 2020, Berkshire repaid €1.0 billion of maturing senior notes and issued €1.0 billion of 0.0% senior notes due in 2025. In April 2020, Berkshire issued ¥195.5 billion (approximately $1.8 billion) of senior notes with maturity dates ranging from 2023 to 2060 and a weighted average interest rate of 1.07%. Borrowings of BHFC, a wholly owned finance subsidiary of Berkshire, consist of senior unsecured notes used to fund manufactured housing loans originated or acquired and equipment held for lease of certain subsidiaries. BHFC borrowings are fully and unconditionally guaranteed by Berkshire. In the first nine months of 2020, BHFC repaid $350 million of maturing senior notes and issued $500 million of 1.85% senior notes due in 2030. In October 2020, BHFC repaid $550 million of maturing senior notes and issued $2.5 billion of senior notes consisting of $750 million of 1.45% senior notes due in 2030 and $1.75 billion of 2.85% senior notes due in 2050. The carrying values of Berkshire and BHFC non-U.S. Dollar denominated senior notes (€6.85 billion, £1.75 billion and ¥625.5 billion par) reflect the applicable foreign currency exchange rates as of the balance sheet dates. The effects of changes in foreign currency exchange rates during the period are recorded in earnings as a component of selling, general and administrative expenses. Changes in the exchange rates resulted in pre-tax losses of $549 million in the third quarter and $447 million in the first nine months of 2020 and pre-tax gains of $383 million in the third quarter and $447 million in the first nine months of 2019. In addition to BHFC borrowings, Berkshire guaranteed approximately $1.2 billion of other subsidiary borrowings at September 30, 2020. Generally, Berkshire’s guarantee of a subsidiary’s debt obligation is an absolute, unconditional and irrevocable guarantee for the full and prompt payment when due of all payment obligations. Weighted Average Interest Rate September 30, 2020 December 31, 2019 Railroad, utilities and energy: Berkshire Hathaway Energy Company (“BHE”) and subsidiaries: BHE senior unsecured debt due 2021-2050 4.5 % $ 11,462 $ 8,581 Subsidiary and other debt due 2020-2064 4.3 % 31,693 30,772 Short-term borrowings 1.8 % 2,400 3,214 Burlington Northern Santa Fe and subsidiaries due 2020-2097 4.6 % 23,245 23,211 $ 68,800 $ 65,778 BHE subsidiary debt represents amounts issued pursuant to separate financing agreements. Substantially all of the assets of certain BHE subsidiaries are, or may be, pledged or encumbered to support or otherwise secure such debt. These borrowing arrangements generally contain various covenants, which pertain to leverage ratios, interest coverage ratios and/or debt service coverage ratios. During the first nine months of 2020, BHE and its subsidiaries issued new term debt of approximately $5.5 billion with maturity dates ranging from 2025 to 2062 and a weighted average interest rate of 3.4%. In the first nine months of 2020, BHE and its subsidiaries repaid $1.9 billion of debt and reduced short-term borrowings. On October 29, 2020, BHE issued $500 million of 1.65% senior notes due in 2031 and $1.5 billion of 2.85% senior notes due in 2051. BNSF’s borrowings are primarily senior unsecured debentures. In April 2020, BNSF issued $575 million of 3.05% senior unsecured debentures due in 2051. During the first nine months of 2020, BNSF repaid $541 million of debt. As of September 30, 2020, BNSF, BHE and their subsidiaries were in compliance with all applicable debt covenants. Berkshire does not guarantee any debt, borrowings or lines of credit of BNSF, BHE or their subsidiaries. As of September 30, 2020, our subsidiaries had unused lines of credit and commercial paper capacity aggregating approximately $9.5 billion to support short-term borrowing programs and provide additional liquidity. Such unused lines of credit included approximately $7.8 billion related to BHE and its subsidiaries.

Fair value measurements

Fair value measurements	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair value measurements	Notes to Consolidated Financial Statements (Continued) Note 17. Fair value measurements Our financial assets and liabilities are summarized below as of September 30, 2020 and December 31, 2019, with fair values shown according to the fair value hierarchy (in millions). The carrying values of cash and cash equivalents, U.S. Treasury Bills, other receivables and accounts payable, accruals and other liabilities are considered to be reasonable estimates of their fair values. Carrying Value Fair Value Quoted Prices (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) September 30, 2020 Investments in fixed maturity securities: U.S. Treasury, U.S. government corporations and agencies $ 3,377 $ 3,377 $ 3,331 $ 46 $ — Foreign governments 9,969 9,969 6,890 3,079 — Corporate bonds 5,574 5,574 — 5,574 — Other 515 515 — 515 — Investments in equity securities 245,317 245,317 236,804 38 8,475 Investment in Kraft Heinz common stock 13,101 9,747 9,747 — — Loans and finance receivables 18,584 19,737 — 2,509 17,228 Derivative contract assets (1) 261 261 2 64 195 Derivative contract liabilities: Railroad, utilities and energy (1) 109 109 5 93 11 Equity index put options 1,547 1,547 — — 1,547 Notes payable and other borrowings: Insurance and other 38,891 43,439 — 43,426 13 Railroad, utilities and energy 68,800 84,315 — 84,315 — December 31, 2019 Investments in fixed maturity securities: U.S. Treasury, U.S. government corporations and agencies $ 3,090 $ 3,090 $ 3,046 $ 44 $ — Foreign governments 8,638 8,638 5,437 3,201 — Corporate bonds 6,352 6,352 — 6,350 2 Other 605 605 — 605 — Investments in equity securities 248,027 248,027 237,271 46 10,710 Investment in Kraft Heinz common stock 13,757 10,456 10,456 — — Loans and finance receivables 17,527 17,861 — 1,809 16,052 Derivative contract assets (1) 145 145 — 23 122 Derivative contract liabilities: Railroad, utilities and energy (1) 76 76 6 59 11 Equity index put options 968 968 — — 968 Notes payable and other borrowings: Insurance and other 37,590 40,589 — 40,569 20 Railroad, utilities and energy 65,778 76,237 — 76,237 — (1) Notes to Consolidated Financial Statements (Continued) Note 17. Fair value measurements (Continued) The fair values of substantially all of our financial instruments were measured using market or income approaches. The hierarchy for measuring fair value consists of Levels 1 through 3, which are described below. Level 1 Level 2 Level 3 Reconciliations of assets and liabilities measured and carried at fair value on a recurring basis with the use of significant unobservable inputs (Level 3) for the nine months ended September 30, 2020 and 2019 follow (in millions). Gains (losses) included in: Balance at beginning of year Earnings Regulatory assets and liabilities Acquisitions, dispositions and settlements Balance at September 30 Investments in fixed maturity and equity securities: 2020 $ 10,407 $ (2,235 ) $ — $ (2 ) $ 8,170 2019 7 499 — 10,002 10,508 Net derivative contract liabilities: 2020 (857 ) (72 ) (36 ) (398 ) (1,363 ) 2019 (2,343 ) 1,528 (41 ) (282 ) (1,138 ) Quantitative information as of September 30, 2020 with respect to significant assets and liabilities measured and carried at fair value on a recurring basis with the use of significant unobservable inputs (Level 3) follows (dollars in millions). Fair Value Principal Valuation Techniques Unobservable Inputs Weighted Average Investments in equity securities: Preferred stock $ 8,159 Discounted cash flow Expected duration 9 years Discount for transferability restrictions and subordination 375 basis points Common stock warrants 10 Warrant pricing model Expected duration 9 years Volatility 28% Derivative contract liabilities 1,547 Option pricing model Volatility 20% Investments in equity securities in the preceding table include our investments in Occidental Preferred and Occidental common stock warrants. See Note 4 for information regarding these investments. These investments are subject to contractual restrictions on transferability and may contain provisions that prevent us from economically hedging our investments. In applying discounted cash flow techniques in valuing the Occidental Preferred, we made assumptions regarding the expected duration of the investment and the effects of subordination in liquidation. In valuing the Occidental common stock warrants, we used a warrant valuation model. While most of the inputs to the model are observable, we made assumptions regarding the expected duration and volatility of the warrants. Notes to Consolidated Financial Statements (Continued) Note 17. Fair value measurements (Continued) Our equity index put option derivative contracts are illiquid and contain contract terms that are not standard in derivatives markets. For example, we are not required to post collateral under most of our contracts. We determine the fair value of the equity index put option contract liabilities based on the Black-Scholes option valuation model. As described in Note 12, we recorded goodwill and indefinite-lived intangible asset impairment charges in the second quarter of 2020. These charges reflected our estimates of fair values of the related reporting units for goodwill and of the indefinite-lived intangible assets, and the related measurements are considered Level 3 measurements. In estimating fair values of reporting units and indefinite-lived intangible assets, we consider the available facts and circumstances concerning the reporting unit and the industries in which it operates. The key assumptions and inputs we generally use in such determinations include forecasting revenues and expenses, cash flows and capital expenditures, as well as the selection of a discount rate and other inputs. These inputs also include our qualitative assessment of risks and uncertainties. We utilized discounted cash flow/earnings methods to develop our estimates of the fair values and we also considered other publicly available information. Estimates of the fair value of reporting units can be significantly affected by expectations of the severity, duration or long-term effects of the COVID-19 pandemic on the reporting unit’s business, which we cannot reliably predict at this time. Consequently, fair value estimates in such instances may be subject to wide variations. We concluded it was appropriate to reflect the increased risks and uncertainties precipitated by the pandemic through a combination of increases in discount rates and reductions to operating and long-term growth assumptions. We also incorporated forecasted operating results that were reduced from what was used in estimating fair value in connection with the 2019 annual impairment test conducted during the fourth quarter.

Common stock

Common stock	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Common stock	Note 18. Common stock Changes i Class A, $5 Par Value (1,650,000 shares authorized) Class B, $0.0033 Par Value (3,225,000,000 shares authorized) Issued Treasury Outstanding Issued Treasury Outstanding Balances at December 31, 2019 719,307 (17,337 ) 701,970 1,408,183,852 (23,702,319 ) 1,384,481,533 Conversions of Class A common stock to Class B common stock (39,694 ) — (39,694 ) 59,541,000 — 59,541,000 Treasury stock acquired — (11,330 ) (11,330 ) — (64,487,462 ) (64,487,462 ) Balances at September 30, 2020 679,613 (28,667 ) 650,946 1,467,724,852 (88,189,781 ) 1,379,535,071 Each Class A common share is entitled to one vote per share. Class B common stock possesses dividend and distribution rights equal to one-fifteen-hundredth one-ten-thousandth Since we have two classes of common stock, we provide earnings per share data on the Consolidated Statements of Earnings for average equivalent Class A shares outstanding and average equivalent Class B shares outstanding. Class B shares are economically equivalent to one-fifteen-hundredth (1/1,500) (1/1,500) Berkshire’s common stock repurchase program permits Berkshire to repurchase its Class A and Class B shares any time that Warren Buffett, Berkshire’s Chairman of the Board and Chief Executive Officer, and Charlie Munger, Vice Chairman of the Board, believe that the repurchase price is below Berkshire’s intrinsic value, conservatively determined. The program continues to allow share repurchases in the open market or through privately negotiated transactions and does not specify a maximum number of shares to be repurchased. However, repurchases will not be made if they would reduce the total value of Berkshire’s consolidated cash, cash equivalents and U.S. Treasury Bills holdings below $20 billion. The repurchase program does not obligate Berkshire to repurchase any specific dollar amount or number of Class A or Class B shares and there is no expiration date to the program.

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income taxes	Note 19. Income taxes Our consolidated effective income tax rates were 19.8% for the third quarter and 30.8% for the first nine months of 2020 and 18.7% for the third quarter and 20.2% for the first nine months of 2019. Our effective income tax rate normally reflects recurring benefits from dividends-received deductions applicable to investments in equity securities and production tax credits related to wind-powered electricity generation placed in service in the U.S. Our periodic effective income tax rate will also vary due to the changes in mix of pre-tax earnings, the magnitude of gains or losses with respect to our investments in equity securities and of non-deductible goodwill impairment charges and other expenses and the underlying income tax rates applicable in the various taxing jurisdictions.

Accumulated other comprehensive

Accumulated other comprehensive income	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Accumulated other comprehensive income	Note 20. Accumulated other comprehensive income A summary of the net changes in after-tax accumulated other comprehensive income attributable to Berkshire Hathaway shareholders for the nine months ending September 30, 2020 and 2019 follows (in millions). Unrealized appreciation of investments, net Foreign currency translation Defined benefit pension plans Other Accumulated other comprehensive income First nine months of 2020 Balance at beginning of year $ 481 $ (4,346 ) $ (1,369 ) $ (9 ) $ (5,243 ) Other comprehensive income, net 29 (28 ) 67 (15 ) 53 Balance at end of period $ 510 $ (4,374 ) $ (1,302 ) $ (24 ) $ (5,190 ) First nine months of 2019 Balance at beginning of year $ 370 $ (4,603 ) $ (816 ) $ 34 $ (5,015 ) Other comprehensive income, net 137 (534 ) 33 (29 ) (393 ) Balance at end of period $ 507 $ (5,137 ) $ (783 ) $ 5 $ (5,408 )

Supplemental cash flow informat

Supplemental cash flow information	9 Months Ended
	Sep. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Supplemental cash flow information	Note 21. Supplemental cash flow information A summary of supplemental cash flow information is presented in the following table (in millions). First Nine Months 2020 2019 Cash paid during the period for: Income taxes $ 2,715 $ 4,395 Interest: Insurance and other 892 879 Railroad, utilities and energy 2,174 2,149 Non-cash investing and financing activities: Non-cash acquisition of equity securities 430 —

Contingencies and commitments

Contingencies and commitments	9 Months Ended
	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Contingencies and commitments	Note 22. Contingencies and commitments We are parties in a variety of legal actions that routinely arise out of the normal course of business, including legal actions seeking to establish liability directly through insurance contracts or indirectly through reinsurance contracts issued by Berkshire subsidiaries. Plaintiffs occasionally seek punitive or exemplary damages. We do not believe that such normal and routine litigation will have a material effect on our financial condition or results of operations. Berkshire and certain of its subsidiaries are also involved in other kinds of legal actions, some of which assert or may assert claims or seek to impose fines and penalties. We believe that any liability that may arise as a result of other pending legal actions will not have a material effect on our consolidated financial condition or results of operations. In July 2020, Berkshire Hathaway Energy (“BHE”) reached a definitive agreement with Dominion Energy, Inc. (“Dominion”) to acquire substantially all of Dominion’s natural gas transmission and storage business, which includes more than 7,700 miles of natural gas transmission pipelines, about 900 billion cubic feet of operated natural gas storage capacity and partial ownership of a liquefied natural gas export, import and storage facility. The agreement provided for an aggregate acquisition price of approximately $4.0 billion and that BHE would also assume approximately $5.7 billion of existing asset-related long-term debt. Notes to Consolidated Financial Statements (Continued) Note 22. Contingencies and commitments (Continued) On October 5, 2020, BHE and Dominion agreed, as permitted under the acquisition agreement, to provide for the acquisition of all originally agreed upon businesses, except for certain pipeline assets (the “Excluded Assets”), for approximately $2.7 billion in cash and BHE’s assumption of approximately $5.3 billion of debt. This acquisition was completed on November 1, 2020. In addition, on October 5, 2020, BHE and Dominion entered into a second acquisition agreement providing for BHE’s acquisition of the Excluded Assets for approximately $1.3 billion in cash and BHE’s assumption of approximately $0.4 billion of debt. The closing of this acquisition is subject to receiving necessary regulatory approvals and other customary closing conditions and is expected to occur in early 2021.

Revenues from contracts with cu

Revenues from contracts with customers	9 Months Ended
	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Revenues from contracts with customers	Note 23. Revenues from contracts with customers We recognize revenue when a good or service is transferred to a customer. A good or service is transferred when or as the customer obtains control of that good or service. Revenues are based on the consideration we expect to receive in connection with our promises to deliver goods and services to our customers. The following tables summarize customer contract revenues disaggregated by reportable segment and the source of the revenue for the third quarter and first nine months of 2020 and 2019 (in millions). Other revenues included in consolidated revenues were primarily insurance premiums earned, interest, dividend and other investment income and leasing revenues, which are not considered to be revenues from contracts with customers under GAAP. Manufacturing McLane Company Service and Retail BNSF Berkshire Hathaway Energy Insurance, Corporate and other Total Three months ending September 30, 2020 Manufactured products: Industrial and commercial products $ 4,889 $ — $ 54 $ — $ — $ — $ 4,943 Building products 4,322 — — — — — 4,322 Consumer products 4,036 — — — — — 4,036 Grocery and convenience store distribution — 7,905 — — — — 7,905 Food and beverage distribution — 3,968 — — — — 3,968 Auto sales — — 2,195 — — — 2,195 Other retail and wholesale distribution 599 — 3,182 — — — 3,781 Service 370 144 865 5,135 1,474 — 7,988 Electricity and natural gas — — — — 4,356 — 4,356 Total 14,216 12,017 6,296 5,135 5,830 — 43,494 Other revenues 929 23 966 14 396 17,202 19,530 $ 15,145 $ 12,040 $ 7,262 $ 5,149 $ 6,226 $ 17,202 $ 63,024 Nine months ending September 30, 2020 Manufactured products: Industrial and commercial products $ 15,639 $ — $ 143 $ — $ — $ — $ 15,782 Building products 11,682 — — — — — 11,682 Consumer products 10,373 — — — — — 10,373 Grocery and convenience store distribution — 23,051 — — — — 23,051 Food and beverage distribution — 11,561 — — — — 11,561 Auto sales — — 5,999 — — — 5,999 Other retail and wholesale distribution 1,691 — 8,735 — — — 10,426 Service 1,105 398 2,460 15,059 3,238 — 22,260 Electricity and natural gas — — — — 11,190 — 11,190 Total 40,490 35,010 17,337 15,059 14,428 — 122,324 Other revenues 2,686 69 2,884 42 964 52,160 58,805 $ 43,176 $ 35,079 $ 20,221 $ 15,101 $ 15,392 $ 52,160 $ 181,129 Notes to Consolidated Financial Statements (Continued) Note 23. Revenues from contracts with customers (Continued) Manufacturing McLane Company Service and Retail BNSF Berkshire Hathaway Energy Insurance, Corporate and other Total Three months ending September 30, 2019 Manufactured products: Industrial and commercial products $ 6,346 $ — $ 44 $ — $ — $ — $ 6,390 Building products 4,101 — — — — — 4,101 Consumer products 3,528 — — — — — 3,528 Grocery and convenience store distribution — 8,298 — — — — 8,298 Food and beverage distribution — 4,202 — — — — 4,202 Auto sales — — 2,250 — — — 2,250 Other retail and wholesale distribution 524 — 2,946 — — — 3,470 Service 445 80 1,034 5,967 1,191 — 8,717 Electricity and natural gas — — — — 4,213 — 4,213 Total 14,944 12,580 6,274 5,967 5,404 — 45,169 Other revenues 937 24 1,080 15 316 17,431 19,803 $ 15,881 $ 12,604 $ 7,354 $ 5,982 $ 5,720 $ 17,431 $ 64,972 Nine months ending September 30, 2019 Manufactured products: Industrial and commercial products $ 19,308 $ — $ 136 $ — $ — $ — $ 19,444 Building products 11,796 — — — — — 11,796 Consumer products 10,487 — — — — — 10,487 Grocery and convenience store distribution — 24,375 — — — — 24,375 Food and beverage distribution — 12,648 — — — — 12,648 Auto sales — — 6,312 — — — 6,312 Other retail and wholesale distribution 1,602 — 8,959 — — — 10,561 Service 1,222 123 3,068 17,517 3,139 — 25,069 Electricity and natural gas — — — — 11,329 — 11,329 Total 44,415 37,146 18,475 17,517 14,468 — 132,021 Other revenues 2,715 68 3,323 41 894 50,186 57,227 $ 47,130 $ 37,214 $ 21,798 $ 17,558 $ 15,362 $ 50,186 $ 189,248 A summary of the transaction price allocated to the significant unsatisfied remaining performance obligations relating to contracts with expected durations in excess of one year as of September 30, 2020 follows (in millions). Performance obligations expected to be satisfied: Less than 12 months Greater than 12 months Total Electricity and natural gas $ 1,642 $ 5,379 $ 7,021 Other sales and service contracts 1,206 2,457 3,663

Business segment data

Business segment data	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Business segment data	Note 24. Business segment data Our operating businesses include a large and diverse group of insurance, manufacturing, service and retailing businesses. We organize our reportable business segments in a manner that reflects how management views those business activities. Certain businesses are grouped together for segment reporting based upon similar products or product lines, marketing, selling and distribution characteristics, even though those business units are operated under separate local management. Revenues and earnings before income taxes by segment for the third quarter and first nine months of 2020 and 2019 were as follows (in millions). Third Quarter First Nine Months 2020 2019 2020 2019 Revenues of Operating Businesses Insurance: Underwriting: GEICO $ 8,540 $ 8,996 $ 26,689 $ 26,487 Berkshire Hathaway Primary Group 2,490 2,387 7,103 6,825 Berkshire Hathaway Reinsurance Group 4,883 3,940 13,464 11,193 Investment income 1,223 1,789 4,486 4,930 Total insurance 17,136 17,112 51,742 49,435 BNSF 5,176 6,021 15,195 17,676 Berkshire Hathaway Energy 6,226 5,720 15,392 15,362 Manufacturing 15,170 15,897 43,238 47,173 McLane Company 12,040 12,604 35,079 37,214 Service and retailing 7,279 7,378 20,272 21,865 63,027 64,732 180,918 188,725 Reconciliation of segments to consolidated amount Corporate, eliminations and other (3 ) 240 211 523 $ 63,024 $ 64,972 $ 181,129 $ 189,248 Third Quarter First Nine Months 2020 2019 2020 2019 Earnings Before Income Taxes of Operating Businesses Insurance: Underwriting: GEICO $ 276 $ 376 $ 3,320 $ 1,539 Berkshire Hathaway Primary Group (126 ) 153 (63 ) 290 Berkshire Hathaway Reinsurance Group (441 ) 52 (2,033 ) (305 ) Investment income 1,220 1,782 4,480 4,916 Total insurance 929 2,363 5,704 6,440 BNSF 1,777 1,941 4,855 5,379 Berkshire Hathaway Energy 1,122 1,061 2,074 2,194 Manufacturing 2,255 2,484 5,765 7,205 McLane Company 96 50 205 220 Service and retailing 779 639 1,745 2,005 6,958 8,538 20,348 23,443 Reconciliation of segments to consolidated amount Investment and derivative gains/losses 31,582 10,926 1,392 41,296 Interest expense, not allocated to segments (116 ) (96 ) (363 ) (312 ) Equity method investments 290 644 333 936 Goodwill and intangible asset impairments (25 ) — (10,659 ) — Corporate, eliminations and other (759 ) 477 (761 ) 532 $ 37,930 $ 20,489 $ 10,290 $ 65,895

New accounting pronouncements (

New accounting pronouncements (Policies)	9 Months Ended
	Sep. 30, 2020
Accounting Changes And Error Corrections [Abstract]
New accounting pronouncements	We adopted Accounting Standards Codification (“ASC”) 326 “Financial Instruments-Credit Losses” on January 1, 2020. ASC 326 provides for the measurement of expected credit losses on financial assets that are carried at amortized cost based on the net amounts expected to be collected. Measurements of expected credit losses therefore include provisions for non-collection, whether the risk is probable or remote. Prior to the adoption of ASC 326, credit losses were measured when non-collection was considered probable based on the prevailing facts and circumstances. We elected to not measure an allowance for expected credit losses on accrued interest and instead reverse uncollectible accrued interest through interest income on a timely basis. Upon adoption of ASC 326, we recorded a charge to retained earnings of $388 million representing the cumulative after-tax increase in our allowances for credit losses, which was primarily related to our manufactured housing loans. Expected credit losses for such financial assets are based on the net present value of future principal payments less estimated expenses related to the charge-off and foreclosure of expected uncollectible loans and include provisions for loans that are not in foreclosure. Our principal credit quality indicator is whether the loans are performing. Expected credit loss estimates consider historical default rates, collateral recovery rates, historical runoff rates, interest rates, reductions of future cash flows for modified loans, the historical time elapsed from last payment until foreclosure, among other matters. In addition, our estimates consider current conditions and reasonable and supportable forecasts. Notes to Consolidated Financial Statements (Continued) Note 2. New accounting pronouncements (Continued) Trade receivables, insurance premium receivables and other receivables are primarily short-term in duration with stated collection terms of less than one year from the date of origination. In establishing credit loss allowances for such receivables, we primarily utilize credit loss history. However, credit loss allowances may be adjusted as a result of current conditions and when we expect reasonable and supportable forecasts to deviate from historical experience. In evaluating expected credit losses of reinsurance recoverables, we review the credit quality of the counterparty and consider credit ratings, right-of-offset provisions within reinsurance contracts and other forms of credit enhancement including, collateral, funds held arrangements, guarantees, as well as other publicly available information. We adopted ASU 2017-04 “Simplifying the Test for Goodwill Impairment” as of January 1, 2020. Under ASU 2017-04, the measurement of a goodwill impairment is represented by the excess of the carrying value over the fair value of the reporting unit and is limited to the carrying value of goodwill. In August 2018, the FASB issued ASU 2018-12 “Targeted Improvements to the Accounting for Long-Duration Contracts.” ASU 2018-12 requires periodic reassessment of actuarial and discount rate assumptions used to value policyholder liabilities and deferred acquisition costs arising from long-duration insurance and reinsurance contracts, with the effects of changes in cash flow assumptions reflected in earnings and the effects of changes in discount rate assumptions reflected in other comprehensive income. Currently, the actuarial and discount rate assumptions are set at the contract inception date and not subsequently changed, except under limited circumstances. ASU 2018-12 requires new disclosures and is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. We are evaluating the effect this standard will have on our Consolidated Financial Statements.

Investments in fixed maturity_2

Investments in fixed maturity securities (Tables)	9 Months Ended
	Sep. 30, 2020
Investments Debt And Equity Securities [Abstract]
Schedule of investments in securities with fixed maturities	Investments in fixed maturity securities as of September 30, 2020 and December 31, 2019 are summarized by type below (in millions). Amortized Cost Unrealized Gains Unrealized Losses Fair Value September 30, 2020 U.S. Treasury, U.S. government corporations and agencies $ 3,311 $ 66 $ — $ 3,377 Foreign governments 9,898 82 (11 ) 9,969 Corporate bonds 5,125 455 (6 ) 5,574 Other 447 70 (2 ) 515 $ 18,781 $ 673 $ (19 ) $ 19,435 December 31, 2019 U.S. Treasury, U.S. government corporations and agencies $ 3,054 $ 37 $ (1 ) $ 3,090 Foreign governments 8,584 63 (9 ) 8,638 Corporate bonds 5,896 459 (3 ) 6,352 Other 539 67 (1 ) 605 $ 18,073 $ 626 $ (14 ) $ 18,685
Schedule of amortized cost and estimated fair value of securities with fixed maturities	The amortized cost and estimated fair value of fixed maturity securities as of September 30, 2020 are summarized below by contractual maturity dates (in millions). Actual maturities may differ from contractual maturities due to early call or prepayment rights held by issuers. Due in one year or less Due after one year through five years Due after five years through ten years Due after ten years Mortgage- backed securities Total Amortized cost $ 9,847 $ 7,885 $ 302 $ 405 $ 342 $ 18,781 Fair value 9,887 8,030 349 764 405 19,435

Investments in equity securit_2

Investments in equity securities (Tables)	9 Months Ended
	Sep. 30, 2020
Investments Debt And Equity Securities [Abstract]
Schedule of investments in equity securities	Investments in equity securities as of September 30, 2020 and December 31, 2019 are summarized in the tables below (in millions). Cost Basis Net Unrealized Gains Fair Value September 30, 2020* Banks, insurance and finance $ 27,145 $ 29,065 $ 56,210 Consumer products 37,016 98,022 135,038 Commercial, industrial and other 41,468 12,601 54,069 $ 105,629 $ 139,688 $ 245,317 * Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion). Cost Basis Net Unrealized Gains Fair Value December 31, 2019* Banks, insurance and finance $ 40,419 $ 61,976 $ 102,395 Consumer products 38,887 60,747 99,634 Commercial, industrial and other 31,034 14,964 45,998 $ 110,340 $ 137,687 $ 248,027 * Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion).

Equity method investments (Tabl

Equity method investments (Tables)	9 Months Ended
	Sep. 30, 2020
Equity Method Investments And Joint Ventures [Abstract]
Summarized unaudited financial information of Kraft Heinz	Summarized consolidated financial information of Kraft Heinz follows (in millions). September 26, 2020 December 28, 2019 Assets $ 98,122 $ 101,450 Liabilities 48,783 49,701 Third Quarter First Nine Months 2020 2019 2020 2019 Sales $ 6,441 $ 6,076 $ 19,246 $ 18,441 Net earnings (loss) attributable to Kraft Heinz common shareholders* 597 899 (676 ) 1,753 *

Investment gains_losses (Tables

Investment gains/losses (Tables)	9 Months Ended
	Sep. 30, 2020
Investments Debt And Equity Securities [Abstract]
Summary of investment gains and losses	Investment gains/losses in the third quarter and first nine months of 2020 and 2019 are summarized as follows (in millions). Third Quarter First Nine Months 2020 2019 2020 2019 Equity securities: Unrealized investment gains during the period on securities held at the end of the period $ 30,837 $ 10,489 $ 16,458 $ 39,546 Investment gains/losses on securities sold during the period 1,330 135 (13,901 ) 464 32,167 10,624 2,557 40,010 Fixed maturity securities: Gross realized gains 12 59 53 71 Gross realized losses (2 ) (2 ) (22 ) (18 ) Other (552 ) 11 (556 ) 16 $ 31,625 $ 10,692 $ 2,032 $ 40,079

Loans and finance receivables (

Loans and finance receivables (Tables)	9 Months Ended
	Sep. 30, 2020
Loans and Finance Receivables [Member]
Schedule of receivables	Loans and finance receivables are summarized as follows (in millions). September 30, 2020 December 31, 2019 Loans and finance receivables before allowances and discounts $ 19,832 $ 18,199 Allowances for credit losses (731 ) (167 ) Unamortized acquisition discounts and points (517 ) (505 ) $ 18,584 $ 17,527
Schedule of reconciliation of allowance for credit losses on loans and finance receivables	Loans and finance receivables are principally installment loans originated or acquired by our manufactured housing business. Reconciliations of the allowance for credit losses on loans and finance receivables for each of the first nine months of 2020 and 2019 follow (in millions). 2020 2019 Balance at beginning of year $ 167 $ 177 Adoption of ASC 326 486 — Provision for credit losses 177 109 Charge-offs, net of recoveries (99 ) (103 ) Balance at September 30 $ 731 $ 183
Manufactured Housing Loan Balances [Member]
Summary of performing and non-performing manufactured housing loans before discounts and allowances by year of loan origination	A summary of performing and non-performing manufactured housing loans before discounts and allowances by year of loan origination as of September 30, 2020 follows (in millions). Loans and Financing Receivables by Origination Year 2020 2019 2018 2017 2016 Prior Total Performing $ 3,328 $ 2,603 $ 1,983 $ 1,471 $ 1,314 $ 6,918 $ 17,617 Non-performing 3 4 6 7 8 49 77 Total $ 3,331 $ 2,607 $ 1,989 $ 1,478 $ 1,322 $ 6,967 $ 17,694

Other receivables (Tables)

Other receivables (Tables)	9 Months Ended
	Sep. 30, 2020
Insurance and Other [Member]
Schedule of receivables	Other receivables of insurance and other businesses are comprised of the following (in millions). September 30, 2020 December 31, 2019 Insurance premiums receivable $ 15,379 $ 13,379 Reinsurance recoverable on unpaid losses 2,857 2,855 Trade receivables 11,840 12,275 Other 4,916 4,327 Allowances for credit losses (603 ) (418 ) $ 34,389 $ 32,418
Railroad, Utilities and Energy [Member]
Schedule of receivables	Receivables of railroad and utilities and energy businesses are comprised of the following (in millions). September 30, 2020 December 31, 2019 Trade receivables $ 3,245 $ 3,120 Other 305 388 Allowances for credit losses (124 ) (91 ) $ 3,426 $ 3,417

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
Schedule of inventories	Inventories are comprised of the following (in millions). September 30, 2020 December 31, 2019 Raw materials $ 4,705 $ 4,492 Work in process and other 2,712 2,700 Finished manufactured goods 4,645 4,821 Goods acquired for resale 7,299 7,839 $ 19,361 $ 19,852

Property, plant and equipment_2

Property, plant and equipment including equipment held for lease (Tables)	9 Months Ended
	Sep. 30, 2020
Schedule of depreciation expense	Depreciation expense for the first nine months of 2020 and 2019 is summarized below (in millions). First Nine Months 2020 2019 Insurance and other $ 1,725 $ 1,660 Railroad, utilities and energy 4,105 3,881 $ 5,830 $ 5,541
Insurance and Other [Member]
Schedule of property, plant and equipment	A summary of property, plant and equipment of our insurance and other businesses follows (in millions). September 30, 2020 December 31, 2019 Land, buildings and improvements $ 13,555 $ 13,259 Machinery and equipment 24,765 24,285 Furniture, fixtures and other 4,689 4,666 43,009 42,210 Accumulated depreciation (21,868 ) (20,772 ) $ 21,141 $ 21,438
Railroad, Utilities and Energy [Member]
Schedule of property, plant and equipment	A summary of property, plant and equipment of railroad and utilities and energy businesses follows (in millions). The utility generation, transmission and distribution systems and interstate natural gas pipeline assets are owned by regulated public utility and natural gas pipeline subsidiaries. September 30, 2020 December 31, 2019 Railroad: Land, track structure and other roadway $ 63,318 $ 62,404 Locomotives, freight cars and other equipment 13,477 13,482 Construction in progress 1,075 748 77,870 76,634 Accumulated depreciation (12,724 ) (12,101 ) 65,146 64,533 Utilities and energy: Utility generation, transmission and distribution systems 82,743 81,127 Interstate natural gas pipeline assets 8,281 8,165 Independent power plants and other assets 8,952 8,817 Construction in progress 5,132 3,732 105,108 101,841 Accumulated depreciation (29,856 ) (28,536 ) 75,252 73,305 $ 140,398 $ 137,838

Equipment held for lease (Table

Equipment held for lease (Tables)	9 Months Ended
	Sep. 30, 2020
Property Plant And Equipment [Abstract]
Schedule of equipment held for lease	Equipment held for lease includes railcars, aircraft, over-the-road trailers, intermodal tank containers, cranes, storage units and furniture. A summary of equipment held for lease follows (in millions). September 30, 2020 December 31, 2019 Railcars $ 9,396 $ 9,260 Aircraft 8,061 8,093 Other 4,887 4,862 22,344 22,215 Accumulated depreciation (7,630 ) (7,150 ) $ 14,714 $ 15,065
Summary of operating lease revenues by type	Operating lease revenues by type for the third quarter and first nine months of 2020 and 2019 were as follows (in millions). Third Quarter First Nine Months 2020 2019 2020 2019 Fixed lease revenue $ 1,047 $ 1,097 $ 3,205 $ 3,289 Variable lease revenue 269 341 700 1,076 $ 1,316 $ 1,438 $ 3,905 $ 4,365

Goodwill and other intangible_2

Goodwill and other intangible assets (Tables)	9 Months Ended
	Sep. 30, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Reconciliation of the change in goodwill	Reconciliations of the changes in the carrying value of goodwill for the first nine months of 2020 and for the year ended December 31, 2019 follow (in millions). September 30, 2020 December 31, 2019 Balance at beginning of year $ 81,882 $ 81,025 Acquisitions of businesses 25 890 Impairment charges (10,021 ) — Other, including foreign currency translation (21 ) (33 ) Balance at end of period $ 71,865 $ 81,882
Schedule of intangible assets	Other intangible assets and related accumulated amortization are summarized as follows (in millions). September 30, 2020 December 31, 2019 Gross carrying amount Accumulated amortization Gross carrying amount Accumulated amortization Insurance and other: Customer relationships $ 27,344 $ 5,548 $ 27,943 $ 5,025 Trademarks and trade names 5,193 774 5,286 759 Patents and technology 4,720 3,255 4,560 3,032 Other 3,319 1,347 3,364 1,286 $ 40,576 $ 10,924 $ 41,153 $ 10,102 Railroad, utilities and energy: Customer relationships $ 678 $ 352 $ 678 $ 324 Trademarks, trade names and other 325 91 325 84 $ 1,003 $ 443 $ 1,003 $ 408

Derivative contracts (Tables)

Derivative contracts (Tables)	9 Months Ended
	Sep. 30, 2020
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative contracts outstanding	The liabilities and related notional values of these contracts follow (in millions). Liabilities Notional Value September 30, 2020 $ 1,547 $ 12,472 December 31, 2019 968 14,385

Unpaid losses and loss adjust_2

Unpaid losses and loss adjustment expenses (Tables)	9 Months Ended
	Sep. 30, 2020
Insurance [Abstract]
Schedule of liability for unpaid claims and claims adjustment expense	A reconciliation of the changes in claim liabilities, excluding liabilities under retroactive reinsurance contracts (see Note 15), for each of the nine months ending September 30, 2020 and 2019 follows (in millions). 2020 2019 Balances at beginning of year: Gross liabilities $ 73,019 $ 68,458 Reinsurance recoverable on unpaid losses (2,855 ) (3,060 ) Net liabilities 70,164 65,398 Incurred losses and loss adjustment expenses: Current accident year events 31,777 31,179 Prior accident years’ events 69 (396 ) Total 31,846 30,783 Paid losses and loss adjustment expenses: Current accident year events (11,691 ) (13,144 ) Prior accident years’ events (15,259 ) (13,967 ) Total (26,950 ) (27,111 ) Foreign currency translation adjustment 124 (178 ) Balances at September 30: Net liabilities 75,184 68,892 Reinsurance recoverable on unpaid losses 2,857 3,105 Gross liabilities $ 78,041 $ 71,997

Retroactive reinsurance contr_2

Retroactive reinsurance contracts (Tables)	9 Months Ended
	Sep. 30, 2020
Insurance [Abstract]
Reconciliation of changes in retroactive reinsurance claim liabilities and deferred charge assets	Reconciliations of the changes in estimated liabilities for retroactive reinsurance unpaid losses and loss adjustment expenses (“claim liabilities”) and related deferred charge reinsurance assumed assets for each of the nine months ending September 30, 2020 and 2019 follow (in millions). 2020 2019 Unpaid losses and loss adjustment expenses Deferred charges reinsurance assumed Unpaid losses and loss adjustment expenses Deferred charges reinsurance assumed Balances at beginning of year $ 42,441 $ (13,747 ) $ 41,834 $ (14,104 ) Incurred losses and loss adjustment expenses: Current year contracts — — 175 (82 ) Prior years’ contracts 131 735 (2 ) 827 Total 131 735 173 745 Paid losses and loss adjustment expenses (786 ) — (643 ) — Balances at September 30 $ 41,786 $ (13,012 ) $ 41,364 $ (13,359 ) Incurred losses and loss adjustment expenses, net of deferred charges $ 866 $ 918

Notes payable and other borro_2

Notes payable and other borrowings (Tables)	9 Months Ended
	Sep. 30, 2020
Schedule of short and long term outstanding debt disclosure	Notes payable and other borrowings are summarized below (dollars in millions). The weighted average interest rates and maturity date ranges shown in the following tables are based on borrowings as of September 30, 2020. Weighted Average Interest Rate September 30, 2020 December 31, 2019 Insurance and other: Berkshire Hathaway Inc. (“Berkshire”): U.S. Dollar denominated due 2020-2047 3.2 % $ 8,320 $ 8,324 Euro denominated due 2021-2035 1.0 % 7,986 7,641 Japanese Yen denominated due 2023-2060 0.6 % 5,902 3,938 Berkshire Hathaway Finance Corporation (“BHFC”): U.S. Dollar denominated due 2020-2049 4.1 % 8,829 8,679 Great Britain Pound denominated due 2039-2059 2.5 % 2,218 2,274 Other subsidiary borrowings due 2020-2045 4.2 % 4,676 5,262 Subsidiary short-term borrowings 2.7 % 960 1,472 $ 38,891 $ 37,590
Railroad, Utilities and Energy [Member]
Schedule of short and long term outstanding debt disclosure	Weighted Average Interest Rate September 30, 2020 December 31, 2019 Railroad, utilities and energy: Berkshire Hathaway Energy Company (“BHE”) and subsidiaries: BHE senior unsecured debt due 2021-2050 4.5 % $ 11,462 $ 8,581 Subsidiary and other debt due 2020-2064 4.3 % 31,693 30,772 Short-term borrowings 1.8 % 2,400 3,214 Burlington Northern Santa Fe and subsidiaries due 2020-2097 4.6 % 23,245 23,211 $ 68,800 $ 65,778

Fair value measurements (Tables

Fair value measurements (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Financial assets and liabilities measured at fair value on a recurring basis	Our financial assets and liabilities are summarized below as of September 30, 2020 and December 31, 2019, with fair values shown according to the fair value hierarchy (in millions). The carrying values of cash and cash equivalents, U.S. Treasury Bills, other receivables and accounts payable, accruals and other liabilities are considered to be reasonable estimates of their fair values. Carrying Value Fair Value Quoted Prices (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) September 30, 2020 Investments in fixed maturity securities: U.S. Treasury, U.S. government corporations and agencies $ 3,377 $ 3,377 $ 3,331 $ 46 $ — Foreign governments 9,969 9,969 6,890 3,079 — Corporate bonds 5,574 5,574 — 5,574 — Other 515 515 — 515 — Investments in equity securities 245,317 245,317 236,804 38 8,475 Investment in Kraft Heinz common stock 13,101 9,747 9,747 — — Loans and finance receivables 18,584 19,737 — 2,509 17,228 Derivative contract assets (1) 261 261 2 64 195 Derivative contract liabilities: Railroad, utilities and energy (1) 109 109 5 93 11 Equity index put options 1,547 1,547 — — 1,547 Notes payable and other borrowings: Insurance and other 38,891 43,439 — 43,426 13 Railroad, utilities and energy 68,800 84,315 — 84,315 — December 31, 2019 Investments in fixed maturity securities: U.S. Treasury, U.S. government corporations and agencies $ 3,090 $ 3,090 $ 3,046 $ 44 $ — Foreign governments 8,638 8,638 5,437 3,201 — Corporate bonds 6,352 6,352 — 6,350 2 Other 605 605 — 605 — Investments in equity securities 248,027 248,027 237,271 46 10,710 Investment in Kraft Heinz common stock 13,757 10,456 10,456 — — Loans and finance receivables 17,527 17,861 — 1,809 16,052 Derivative contract assets (1) 145 145 — 23 122 Derivative contract liabilities: Railroad, utilities and energy (1) 76 76 6 59 11 Equity index put options 968 968 — — 968 Notes payable and other borrowings: Insurance and other 37,590 40,589 — 40,569 20 Railroad, utilities and energy 65,778 76,237 — 76,237 — (1)
Reconciliations of significant assets and liabilities measured and carried at fair value on a recurring basis with the use of significant unobservable inputs (Level 3)	Reconciliations of assets and liabilities measured and carried at fair value on a recurring basis with the use of significant unobservable inputs (Level 3) for the nine months ended September 30, 2020 and 2019 follow (in millions). Gains (losses) included in: Balance at beginning of year Earnings Regulatory assets and liabilities Acquisitions, dispositions and settlements Balance at September 30 Investments in fixed maturity and equity securities: 2020 $ 10,407 $ (2,235 ) $ — $ (2 ) $ 8,170 2019 7 499 — 10,002 10,508 Net derivative contract liabilities: 2020 (857 ) (72 ) (36 ) (398 ) (1,363 ) 2019 (2,343 ) 1,528 (41 ) (282 ) (1,138 )
Fair value assets and liabilities measured on recurring basis, unobservable inputs, additional information	Quantitative information as of September 30, 2020 with respect to significant assets and liabilities measured and carried at fair value on a recurring basis with the use of significant unobservable inputs (Level 3) follows (dollars in millions). Fair Value Principal Valuation Techniques Unobservable Inputs Weighted Average Investments in equity securities: Preferred stock $ 8,159 Discounted cash flow Expected duration 9 years Discount for transferability restrictions and subordination 375 basis points Common stock warrants 10 Warrant pricing model Expected duration 9 years Volatility 28% Derivative contract liabilities 1,547 Option pricing model Volatility 20%

Common stock (Tables)

Common stock (Tables)	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Changes in issued, treasury and outstanding Berkshire common stock	Changes i Class A, $5 Par Value (1,650,000 shares authorized) Class B, $0.0033 Par Value (3,225,000,000 shares authorized) Issued Treasury Outstanding Issued Treasury Outstanding Balances at December 31, 2019 719,307 (17,337 ) 701,970 1,408,183,852 (23,702,319 ) 1,384,481,533 Conversions of Class A common stock to Class B common stock (39,694 ) — (39,694 ) 59,541,000 — 59,541,000 Treasury stock acquired — (11,330 ) (11,330 ) — (64,487,462 ) (64,487,462 ) Balances at September 30, 2020 679,613 (28,667 ) 650,946 1,467,724,852 (88,189,781 ) 1,379,535,071

Accumulated other comprehensi_2

Accumulated other comprehensive income (Tables)	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Schedule of accumulated other comprehensive income	A summary of the net changes in after-tax accumulated other comprehensive income attributable to Berkshire Hathaway shareholders for the nine months ending September 30, 2020 and 2019 follows (in millions). Unrealized appreciation of investments, net Foreign currency translation Defined benefit pension plans Other Accumulated other comprehensive income First nine months of 2020 Balance at beginning of year $ 481 $ (4,346 ) $ (1,369 ) $ (9 ) $ (5,243 ) Other comprehensive income, net 29 (28 ) 67 (15 ) 53 Balance at end of period $ 510 $ (4,374 ) $ (1,302 ) $ (24 ) $ (5,190 ) First nine months of 2019 Balance at beginning of year $ 370 $ (4,603 ) $ (816 ) $ 34 $ (5,015 ) Other comprehensive income, net 137 (534 ) 33 (29 ) (393 ) Balance at end of period $ 507 $ (5,137 ) $ (783 ) $ 5 $ (5,408 )

Supplemental cash flow inform_2

Supplemental cash flow information (Tables)	9 Months Ended
	Sep. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Schedule of supplemental cash flow information	A summary of supplemental cash flow information is presented in the following table (in millions). First Nine Months 2020 2019 Cash paid during the period for: Income taxes $ 2,715 $ 4,395 Interest: Insurance and other 892 879 Railroad, utilities and energy 2,174 2,149 Non-cash investing and financing activities: Non-cash acquisition of equity securities 430 —

Revenues from contracts with _2

Revenues from contracts with customers (Tables)	9 Months Ended
	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Revenue from contracts with customers disaggregated by reportable segment and source of revenue	Note 23. Revenues from contracts with customers We recognize revenue when a good or service is transferred to a customer. A good or service is transferred when or as the customer obtains control of that good or service. Revenues are based on the consideration we expect to receive in connection with our promises to deliver goods and services to our customers. The following tables summarize customer contract revenues disaggregated by reportable segment and the source of the revenue for the third quarter and first nine months of 2020 and 2019 (in millions). Other revenues included in consolidated revenues were primarily insurance premiums earned, interest, dividend and other investment income and leasing revenues, which are not considered to be revenues from contracts with customers under GAAP. Manufacturing McLane Company Service and Retail BNSF Berkshire Hathaway Energy Insurance, Corporate and other Total Three months ending September 30, 2020 Manufactured products: Industrial and commercial products $ 4,889 $ — $ 54 $ — $ — $ — $ 4,943 Building products 4,322 — — — — — 4,322 Consumer products 4,036 — — — — — 4,036 Grocery and convenience store distribution — 7,905 — — — — 7,905 Food and beverage distribution — 3,968 — — — — 3,968 Auto sales — — 2,195 — — — 2,195 Other retail and wholesale distribution 599 — 3,182 — — — 3,781 Service 370 144 865 5,135 1,474 — 7,988 Electricity and natural gas — — — — 4,356 — 4,356 Total 14,216 12,017 6,296 5,135 5,830 — 43,494 Other revenues 929 23 966 14 396 17,202 19,530 $ 15,145 $ 12,040 $ 7,262 $ 5,149 $ 6,226 $ 17,202 $ 63,024 Nine months ending September 30, 2020 Manufactured products: Industrial and commercial products $ 15,639 $ — $ 143 $ — $ — $ — $ 15,782 Building products 11,682 — — — — — 11,682 Consumer products 10,373 — — — — — 10,373 Grocery and convenience store distribution — 23,051 — — — — 23,051 Food and beverage distribution — 11,561 — — — — 11,561 Auto sales — — 5,999 — — — 5,999 Other retail and wholesale distribution 1,691 — 8,735 — — — 10,426 Service 1,105 398 2,460 15,059 3,238 — 22,260 Electricity and natural gas — — — — 11,190 — 11,190 Total 40,490 35,010 17,337 15,059 14,428 — 122,324 Other revenues 2,686 69 2,884 42 964 52,160 58,805 $ 43,176 $ 35,079 $ 20,221 $ 15,101 $ 15,392 $ 52,160 $ 181,129 Manufacturing McLane Company Service and Retail BNSF Berkshire Hathaway Energy Insurance, Corporate and other Total Three months ending September 30, 2019 Manufactured products: Industrial and commercial products $ 6,346 $ — $ 44 $ — $ — $ — $ 6,390 Building products 4,101 — — — — — 4,101 Consumer products 3,528 — — — — — 3,528 Grocery and convenience store distribution — 8,298 — — — — 8,298 Food and beverage distribution — 4,202 — — — — 4,202 Auto sales — — 2,250 — — — 2,250 Other retail and wholesale distribution 524 — 2,946 — — — 3,470 Service 445 80 1,034 5,967 1,191 — 8,717 Electricity and natural gas — — — — 4,213 — 4,213 Total 14,944 12,580 6,274 5,967 5,404 — 45,169 Other revenues 937 24 1,080 15 316 17,431 19,803 $ 15,881 $ 12,604 $ 7,354 $ 5,982 $ 5,720 $ 17,431 $ 64,972 Nine months ending September 30, 2019 Manufactured products: Industrial and commercial products $ 19,308 $ — $ 136 $ — $ — $ — $ 19,444 Building products 11,796 — — — — — 11,796 Consumer products 10,487 — — — — — 10,487 Grocery and convenience store distribution — 24,375 — — — — 24,375 Food and beverage distribution — 12,648 — — — — 12,648 Auto sales — — 6,312 — — — 6,312 Other retail and wholesale distribution 1,602 — 8,959 — — — 10,561 Service 1,222 123 3,068 17,517 3,139 — 25,069 Electricity and natural gas — — — — 11,329 — 11,329 Total 44,415 37,146 18,475 17,517 14,468 — 132,021 Other revenues 2,715 68 3,323 41 894 50,186 57,227 $ 47,130 $ 37,214 $ 21,798 $ 17,558 $ 15,362 $ 50,186 $ 189,248
Transaction price allocated to significant unsatisfied remaining performance obligations	A summary of the transaction price allocated to the significant unsatisfied remaining performance obligations relating to contracts with expected durations in excess of one year as of September 30, 2020 follows (in millions). Performance obligations expected to be satisfied: Less than 12 months Greater than 12 months Total Electricity and natural gas $ 1,642 $ 5,379 $ 7,021 Other sales and service contracts 1,206 2,457 3,663

Business segment data (Tables)

Business segment data (Tables)	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Schedule of revenues and earnings or loss before income taxes by segment	Our operating businesses include a large and diverse group of insurance, manufacturing, service and retailing businesses. We organize our reportable business segments in a manner that reflects how management views those business activities. Certain businesses are grouped together for segment reporting based upon similar products or product lines, marketing, selling and distribution characteristics, even though those business units are operated under separate local management. Revenues and earnings before income taxes by segment for the third quarter and first nine months of 2020 and 2019 were as follows (in millions). Third Quarter First Nine Months 2020 2019 2020 2019 Revenues of Operating Businesses Insurance: Underwriting: GEICO $ 8,540 $ 8,996 $ 26,689 $ 26,487 Berkshire Hathaway Primary Group 2,490 2,387 7,103 6,825 Berkshire Hathaway Reinsurance Group 4,883 3,940 13,464 11,193 Investment income 1,223 1,789 4,486 4,930 Total insurance 17,136 17,112 51,742 49,435 BNSF 5,176 6,021 15,195 17,676 Berkshire Hathaway Energy 6,226 5,720 15,392 15,362 Manufacturing 15,170 15,897 43,238 47,173 McLane Company 12,040 12,604 35,079 37,214 Service and retailing 7,279 7,378 20,272 21,865 63,027 64,732 180,918 188,725 Reconciliation of segments to consolidated amount Corporate, eliminations and other (3 ) 240 211 523 $ 63,024 $ 64,972 $ 181,129 $ 189,248 Third Quarter First Nine Months 2020 2019 2020 2019 Earnings Before Income Taxes of Operating Businesses Insurance: Underwriting: GEICO $ 276 $ 376 $ 3,320 $ 1,539 Berkshire Hathaway Primary Group (126 ) 153 (63 ) 290 Berkshire Hathaway Reinsurance Group (441 ) 52 (2,033 ) (305 ) Investment income 1,220 1,782 4,480 4,916 Total insurance 929 2,363 5,704 6,440 BNSF 1,777 1,941 4,855 5,379 Berkshire Hathaway Energy 1,122 1,061 2,074 2,194 Manufacturing 2,255 2,484 5,765 7,205 McLane Company 96 50 205 220 Service and retailing 779 639 1,745 2,005 6,958 8,538 20,348 23,443 Reconciliation of segments to consolidated amount Investment and derivative gains/losses 31,582 10,926 1,392 41,296 Interest expense, not allocated to segments (116 ) (96 ) (363 ) (312 ) Equity method investments 290 644 333 936 Goodwill and intangible asset impairments (25 ) — (10,659 ) — Corporate, eliminations and other (759 ) 477 (761 ) 532 $ 37,930 $ 20,489 $ 10,290 $ 65,895

General - Narrative (Detail)

General - Narrative (Detail)	6 Months Ended
	Oct. 07, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Reduction in premium rate of insurance policies program percentage	15.00%

New accounting pronouncements -

New accounting pronouncements - Narrative (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Retained earnings	$ 408,791		$ 402,493
ASU 2016-13 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adopted	true
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2020
ASU 2016-13 [Member] | Cumulative effect, period of adoption, adjustment [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Retained earnings		$ (388)
ASU 2017-04 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adopted	true
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2020

Investments in fixed maturity_3

Investments in fixed maturity securities (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Amortized cost of fixed maturity securities	$ 18,781	$ 18,073
Unrealized gains on fixed maturity securities	673	626
Unrealized losses on fixed maturity securities	(19)	(14)
Fair value of fixed maturity securities	19,435	18,685
U.S. Treasury, U.S. government corporations and agencies [Member]
Summary of Investment Holdings [Line Items]
Amortized cost of fixed maturity securities	3,311	3,054
Unrealized gains on fixed maturity securities	66	37
Unrealized losses on fixed maturity securities		(1)
Fair value of fixed maturity securities	3,377	3,090
Foreign governments [Member]
Summary of Investment Holdings [Line Items]
Amortized cost of fixed maturity securities	9,898	8,584
Unrealized gains on fixed maturity securities	82	63
Unrealized losses on fixed maturity securities	(11)	(9)
Fair value of fixed maturity securities	9,969	8,638
Corporate bonds [Member]
Summary of Investment Holdings [Line Items]
Amortized cost of fixed maturity securities	5,125	5,896
Unrealized gains on fixed maturity securities	455	459
Unrealized losses on fixed maturity securities	(6)	(3)
Fair value of fixed maturity securities	5,574	6,352
Other [Member]
Summary of Investment Holdings [Line Items]
Amortized cost of fixed maturity securities	447	539
Unrealized gains on fixed maturity securities	70	67
Unrealized losses on fixed maturity securities	(2)	(1)
Fair value of fixed maturity securities	$ 515	$ 605

Investments in fixed maturity_4

Investments in fixed maturity securities - Narrative (Detail)	Sep. 30, 2020
Foreign governments [Member] | AA or Higher Credit Rating [Member]
Summary of Investment Holdings [Line Items]
Percentage of fixed maturity investments by credit rating	87.00%

Investments in fixed maturity_5

Investments in fixed maturity securities - Amortized cost and estimated fair value of securities with fixed maturities (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Due in one year or less - amortized cost	$ 9,847
Due after one year through five years - amortized cost	7,885
Due after five years through ten years - amortized cost	302
Due after ten years - amortized cost	405
Amortized cost of fixed maturity securities	18,781	$ 18,073
Due in one year or less - fair value	9,887
Due after one year through five years - fair value	8,030
Due after five years through ten years - fair value	349
Due after ten years - fair value	764
Fair value of fixed maturity securities	19,435	$ 18,685
Mortgage-backed securities [Member]
Summary of Investment Holdings [Line Items]
Amortized cost of mortgage-backed securities	342
Fair value of mortgage-backed securities	$ 405

Investments in equity securit_3

Investments in equity securities (Detail) - USD ($) $ in Millions	Sep. 30, 2020		Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Cost Basis	$ 105,629		$ 110,340
Net Unrealized Gains	139,688		137,687
Fair Value	245,317	[1]	248,027	[2]
Banks, insurance and finance [Member]
Summary of Investment Holdings [Line Items]
Cost Basis	27,145		40,419
Net Unrealized Gains	29,065		61,976
Fair Value	56,210		102,395
Consumer products [Member]
Summary of Investment Holdings [Line Items]
Cost Basis	37,016		38,887
Net Unrealized Gains	98,022		60,747
Fair Value	135,038		99,634
Commercial, industrial and other [Member]
Summary of Investment Holdings [Line Items]
Cost Basis	41,468		31,034
Net Unrealized Gains	12,601		14,964
Fair Value	$ 54,069		$ 45,998
[1]	Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion).
[2]	Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion).

Investments in equity securit_4

Investments in equity securities (Parenthetical) (Detail) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)Company		Dec. 31, 2019USD ($)Company
Summary of Investment Holdings [Line Items]
Fair value of investments	$ 245,317	[1]	$ 248,027	[2]
American Express Company [Member]
Summary of Investment Holdings [Line Items]
Fair value of investments	15,200		18,900
Apple Inc. [Member]
Summary of Investment Holdings [Line Items]
Fair value of investments	111,700		73,700
Bank of America Corporation [Member]
Summary of Investment Holdings [Line Items]
Fair value of investments	24,900		33,400
The Coca-Cola Company [Member]
Summary of Investment Holdings [Line Items]
Fair value of investments	$ 19,700		$ 22,100
Equity Securities [Member] | Investment Concentration [Member]
Summary of Investment Holdings [Line Items]
Concentration percentage	70.00%		60.00%
Number of companies in concentration percentage | Company	4		4
[1]	Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion).
[2]	Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion).

Investments in equity securit_5

Investments in equity securities - Narrative (Detail) - Investment Commitment [Member] - USD ($) $ / shares in Units, $ in Billions	Aug. 03, 2020	Aug. 08, 2019	Sep. 30, 2020
Summary of Investment Holdings [Line Items]
Investment commitment description			On August 8, 2019, Berkshire invested a total of $10 billion in Occidental Corporation (“Occidental”) newly issued Occidental Cumulative Perpetual Preferred Stock with an aggregate liquidation value of $10 billion, and warrants to purchase up to 80 million shares of Occidental common stock at an exercise price of $62.50 per share. In accordance with the terms of the warrants, on August 3, 2020, the number of shares of common stock that can be purchased was increased to 83.86 million shares and the exercise price was reduced to $59.62 per share. The preferred stock accrues dividends at 8% per annum and is redeemable at the option of Occidental commencing in 2029 at a redemption price equal to 105% of the liquidation preference plus any accumulated and unpaid dividends, or mandatorily under certain specified capital return events. Dividends on the preferred stock may be paid in cash or, at Occidental’s option, in shares of Occidental common stock. The warrants are exercisable in whole or in part until one year after the redemption of the preferred stock. Our investments in Occidental are included in the commercial, industrial and other category in the preceding tables.
Occidental Corporation [Member] | Cumulative Perpetual Preferred Stock and Warrants [Member]
Summary of Investment Holdings [Line Items]
Investment commitment amount		$ 10
Occidental Corporation [Member] | Cumulative Perpetual Preferred Stock [Member]
Summary of Investment Holdings [Line Items]
Investment in preferred stock, liquidation value		$ 10
Investment in preferred stock, stated dividend rate		8.00%
Investment in preferred stock, redemption year start		2029
Investment in preferred stock, redemption price percentage of liquidation preference		105.00%
Occidental Corporation [Member] | Warrant [Member]
Summary of Investment Holdings [Line Items]
Number of common shares that can be purchased	83,860,000	80,000,000
Exercise price for warrants, per share		$ 62.50
Exercise price for warrants, per share	$ 59.62

Equity method investments - Nar

Equity method investments - Narrative (Detail)	3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)shares	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Sep. 30, 2020USD ($)shares	Sep. 30, 2019USD ($)	Dec. 31, 2017StoreLocationgal	Dec. 31, 2019USD ($)
Schedule of Equity Method Investments [Line Items]
Equity method earnings (losses)	$ 290,000,000	$ 644,000,000		$ 333,000,000	$ 936,000,000
Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of retail | Store						950
Pilot Travel Centers LLC [Member] | U.S. States [Member]
Schedule of Equity Method Investments [Line Items]
Number of fueling locations | Location						44
Pilot Travel Centers LLC [Member] | Canadian Provinces [Member]
Schedule of Equity Method Investments [Line Items]
Number of fueling locations | Location						6
Pilot Travel Centers LLC [Member] | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Gallons of fuel purchased annually | gal						11,000,000,000
Pilot Travel Centers LLC [Member] | Berkshire Hathaway Inc. (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage						38.60%
Pilot Travel Centers LLC [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Agreement to Acquire Additional Interest in 2023 [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of additional interest to be acquired						41.40%
Haslam Family [Member] | Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Majority ownership percentage						50.10%
Haslam Family [Member] | Pilot Travel Centers LLC [Member] | Agreement to Acquire Additional Interest in 2023 [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage						20.00%
Third Party [Member] | Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage						11.30%
The Kraft Heinz Company [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares owned | shares	325,442,152			325,442,152
Equity method investment ownership percentage	26.60%			26.60%
Equity method investments, fair value	$ 9,700,000,000			$ 9,700,000,000			$ 10,500,000,000
Equity method investments, carrying value	13,100,000,000			13,100,000,000			13,800,000,000
Equity method earnings (losses)	159,000,000		$ 228,000,000	(180,000,000)	467,000,000
Goodwill and identifiable intangible asset impairment charges from equity method investments				850,000,000	293,000,000
Common stock dividends received				391,000,000	391,000,000
Amount of difference between carrying value and fair value based on quoted market price	$ 3,400,000,000			$ 3,400,000,000
Difference between carrying value and fair value percentage	26.00%			26.00%
Berkadia Commercial Mortgage LLC, Pilot Travel Centers LLC, and Electric Transmission Texas, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments, carrying value	$ 4,100,000,000			$ 4,100,000,000			$ 3,700,000,000
Equity method earnings (losses)				$ 513,000,000	$ 491,000,000
Berkadia Commercial Mortgage LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%
Commercial paper outstanding	$ 1,470,000,000			$ 1,470,000,000
Berkadia Commercial Mortgage LLC [Member] | Commercial Paper [Member]
Schedule of Equity Method Investments [Line Items]
Maximum outstanding balance of commercial paper borrowings	$ 1,500,000,000			$ 1,500,000,000
Berkadia Commercial Mortgage LLC [Member] | Jefferies Financial Group Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%
Electric Transmission Texas, LLC [Member] | Berkshire Hathaway Energy Company Subsidiary [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%
Electric Transmission Texas, LLC [Member] | American Electric Power [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%

Equity method investments - Una

Equity method investments - Unaudited financial information (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 26, 2020	Dec. 31, 2019	Dec. 28, 2019
Schedule of Equity Method Investments [Line Items]
Assets		$ 829,946		$ 829,946			$ 817,729
Liabilities		410,731		410,731			$ 389,166
Sales		63,024	$ 64,972	181,129	$ 189,248
The Kraft Heinz Company [Member]
Schedule of Equity Method Investments [Line Items]
Assets						$ 98,122		$ 101,450
Liabilities						$ 48,783		$ 49,701
Sales		6,441	6,076	19,246	18,441
Net earnings (loss) attributable to Kraft Heinz common shareholders*	[1]	$ 597	$ 899	$ (676)	$ 1,753
[1]	Includes goodwill and identifiable intangible asset impairment charges of approximately

Equity method investments - U_2

Equity method investments - Unaudited financial information (Parenthetical) (Detail) - USD ($) $ in Billions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
The Kraft Heinz Company [Member]
Schedule of Equity Method Investments [Line Items]
Goodwill and identifiable intangible asset impairment charges	$ 3.2	$ 1.1

Investment gains_losses (Detail

Investment gains/losses (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Investments Debt And Equity Securities [Abstract]
Equity securities - Unrealized investment gains during the period on securities held at the end of the period	$ 30,837	$ 10,489	$ 16,458	$ 39,546
Investment gains/losses on securities sold during the period	1,330	135	(13,901)	464
Equity securities - Investment gains (losses), total	32,167	10,624	2,557	40,010
Fixed maturity securities - Gross realized gains	12	59	53	71
Fixed maturity securities - Gross realized losses	(2)	(2)	(22)	(18)
Other	(552)	11	(556)	16
Investment gains (losses)	$ 31,625	$ 10,692	$ 2,032	$ 40,079

Investment gains_losses - Narra

Investment gains/losses - Narrative (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Investments Debt And Equity Securities [Abstract]
Sales of equity securities			$ 28,564	$ 7,127
Taxable gains (loss) on sales of equity securities	$ 3,900	$ 609	$ 666	$ 1,960

Loans and finance receivables_2

Loans and finance receivables (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Loans and finance receivables before allowances and discounts	$ 19,832	$ 18,199
Allowances for credit losses	(731)	(167)	$ (183)	$ (177)
Unamortized acquisition discounts and points	(517)	(505)
Loans and finance receivables	$ 18,584	$ 17,527

Loans and finance receivables -

Loans and finance receivables - Schedule of reconciliation of allowance for credit losses on loans and finance receivables (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Allowance For Credit Loss [Abstract]
Balance at beginning of year	$ 167	$ 177
Adoption of ASC 326	486
Provision for credit losses	177	109
Charge-offs, net of recoveries	(99)	(103)
Balance at September 30	$ 731	$ 183

Loans and finance receivables_3

Loans and finance receivables - Narrative (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Seritage Growth Properties [Member] | Term Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term loan facility amount	$ 2,000,000,000
Expiration date of term loan	Jul. 31, 2023
Outstanding loan balance	$ 1,600,000,000	$ 1,600,000,000
Lee Enterprises, Inc. [Member] | Term Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding loan balance	$ 538,000,000
Loans and Finance Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percent of manufactured housing loan balances evaluated collectively for impairment	99.00%
Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percent of loan balances considered to be current as to payment status	97.00%

Loans and finance receivables_4

Loans and finance receivables - Summary of performing and non-performing manufactured housing loans before discounts and allowances by year of loan origination (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, Total	$ 19,832	$ 18,199
Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2020	3,331
Loans and financing receivables by origination year, 2019	2,607
Loans and financing receivables by origination year, 2018	1,989
Loans and financing receivables by origination year, 2017	1,478
Loans and financing receivables by origination year, 2016	1,322
Loans and financing receivables by origination year, Prior	6,967
Loans and financing receivables by origination year, Total	17,694
Performing [Member] | Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2020	3,328
Loans and financing receivables by origination year, 2019	2,603
Loans and financing receivables by origination year, 2018	1,983
Loans and financing receivables by origination year, 2017	1,471
Loans and financing receivables by origination year, 2016	1,314
Loans and financing receivables by origination year, Prior	6,918
Loans and financing receivables by origination year, Total	17,617
Non-Performing [Member] | Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2020	3
Loans and financing receivables by origination year, 2019	4
Loans and financing receivables by origination year, 2018	6
Loans and financing receivables by origination year, 2017	7
Loans and financing receivables by origination year, 2016	8
Loans and financing receivables by origination year, Prior	49
Loans and financing receivables by origination year, Total	$ 77

Other receivables (Detail)

Other receivables (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Reinsurance recoverable on unpaid losses	$ 2,857	$ 2,855	$ 3,105	$ 3,060
Insurance and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Insurance premiums receivable	15,379	13,379
Reinsurance recoverable on unpaid losses	2,857	2,855
Trade receivables	11,840	12,275
Other	4,916	4,327
Allowances for credit losses	(603)	(418)
Other receivables	34,389	32,418
Railroad, Utilities and Energy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade receivables	3,245	3,120
Other	305	388
Allowances for credit losses	(124)	(91)
Receivables	$ 3,426	$ 3,417

Other receivables - Narrative (

Other receivables - Narrative (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)
Receivables [Abstract]
Provisions for credit losses on receivables	$ 449

Inventories (Detail)

Inventories (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 4,705	$ 4,492
Work in process and other	2,712	2,700
Finished manufactured goods	4,645	4,821
Goods acquired for resale	7,299	7,839
Total inventory	$ 19,361	$ 19,852

Property, plant and equipment (

Property, plant and equipment (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Insurance and Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 43,009	$ 42,210
Property, plant and equipment, accumulated depreciation	(21,868)	(20,772)
Total property, plant and equipment, net	21,141	21,438
Insurance and Other [Member] | Land, buildings and improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	13,555	13,259
Insurance and Other [Member] | Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	24,765	24,285
Insurance and Other [Member] | Furniture, fixtures and other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,689	4,666
Railroad [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	77,870	76,634
Property, plant and equipment, accumulated depreciation	(12,724)	(12,101)
Total property, plant and equipment, net	65,146	64,533
Railroad [Member] | Land, track structure and other roadway [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	63,318	62,404
Railroad [Member] | Locomotives, freight cars and other equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	13,477	13,482
Railroad [Member] | Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,075	748
Utilities and Energy [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	105,108	101,841
Property, plant and equipment, accumulated depreciation	(29,856)	(28,536)
Total property, plant and equipment, net	75,252	73,305
Utilities and Energy [Member] | Utility generation, transmission and distribution systems [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	82,743	81,127
Utilities and Energy [Member] | Interstate natural gas pipeline assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	8,281	8,165
Utilities and Energy [Member] | Independent power plants and other assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	8,952	8,817
Utilities and Energy [Member] | Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,132	3,732
Railroad, Utilities and Energy [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, net	$ 140,398	$ 137,838

Property, plant and equipment -

Property, plant and equipment - Depreciation expense (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 5,830	$ 5,541
Insurance and Other [Member]
Property, Plant and Equipment [Line Items]
Depreciation expense	1,725	1,660
Railroad, Utilities and Energy [Member]
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 4,105	$ 3,881

Equipment held for lease (Detai

Equipment held for lease (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	$ 22,344	$ 22,215
Equipment held for lease, accumulated depreciation	(7,630)	(7,150)
Equipment held for lease, net	14,714	15,065
Railcars [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	9,396	9,260
Aircraft [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	8,061	8,093
Other [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	$ 4,887	$ 4,862

Equipment held for lease - Narr

Equipment held for lease - Narrative (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Leases [Abstract]
Depreciation expense for equipment held for lease	$ 900	$ 880

Equipment held for lease - Summ

Equipment held for lease - Summary of operating lease revenues by type (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating Leases Lease Income [Abstract]
Fixed lease revenue	$ 1,047	$ 1,097	$ 3,205	$ 3,289
Variable lease revenue	269	341	700	1,076
Total	$ 1,316	$ 1,438	$ 3,905	$ 4,365

Goodwill and other intangible_3

Goodwill and other intangible assets - Goodwill (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at beginning of year		$ 81,882	$ 81,025
Acquisitions of businesses		25	890
Impairment charges	$ (10,000)	(10,021)
Other, including foreign currency translation		(21)	(33)
Balance at end of period		$ 71,865	$ 81,882

Goodwill and other intangible_4

Goodwill and other intangible assets - Intangible assets (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Insurance and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 40,576	$ 41,153
Accumulated amortization	10,924	10,102
Railroad, Utilities and Energy [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,003	1,003
Accumulated amortization	443	408
Trademarks and trade names [Member] | Insurance and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	5,193	5,286
Accumulated amortization	774	759
Customer relationships [Member] | Insurance and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	27,344	27,943
Accumulated amortization	5,548	5,025
Customer relationships [Member] | Railroad, Utilities and Energy [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	678	678
Accumulated amortization	352	324
Other intangible assets [Member] | Insurance and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	3,319	3,364
Accumulated amortization	1,347	1,286
Trademarks, Trade Names and Other [Member] | Railroad, Utilities and Energy [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	325	325
Accumulated amortization	91	84
Patents and technology [Member] | Insurance and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Gross carrying amount	4,720	4,560
Accumulated amortization	$ 3,255	$ 3,032

Goodwill and other intangible_5

Goodwill and other intangible assets - Intangible assets - Narrative (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Goodwill [Line Items]
Intangible asset amortization expense		$ 962	$ 986
Intangible assets with indefinite lives, excluding goodwill		18,300		$ 19,000
Pre tax goodwill impairment	$ 10,000	$ 10,021
Pre tax intangible assets impairment charges	638
PCC [Member]
Goodwill [Line Items]
Pre tax impairment charges	10,000
Goodwill and indefinite-lived intangible assets	$ 31,000

Derivative contracts (Detail)

Derivative contracts (Detail) - Not Designated as Hedging Instrument [Member] - Equity Index Put Options [Member] - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Liabilities	$ 1,547	$ 968
Notional Value	$ 12,472	$ 14,385

Derivative contracts - Narrativ

Derivative contracts - Narrative (Detail) - Not Designated as Hedging Instrument [Member] - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Derivative [Line Items]
Collateral posting requirements under contracts with collateral provisions	$ 0		$ 0
Equity Index Put Options [Member]
Derivative [Line Items]
Derivative contract pre-tax gains (losses)	(43,000,000)	$ 234,000,000	$ (640,000,000)	$ 1,217,000,000
Derivative maturity month and year			2023-02
Weighted average life of unexpired derivative contracts			1 year 3 months
Premiums received at contract inception dates	2,100,000,000		$ 2,100,000,000
Aggregate intrinsic value of equity index put option contracts	$ 1,200,000,000		$ 1,200,000,000		$ 397,000,000
Equity Index Put Options [Member] | Maximum [Member]
Derivative [Line Items]
Derivative inception month and year			2008-03

Unpaid losses and loss adjust_3

Unpaid losses and loss adjustment expenses - Reconciliations of changes in claim liabilities (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Gross liabilities at beginning of year	$ 73,019	$ 68,458
Reinsurance recoverable on unpaid losses at beginning of year	(2,855)	(3,060)
Net liabilities at beginning of year	70,164	65,398
Net liabilities at end of period	75,184	68,892
Reinsurance recoverable on unpaid losses at end of period	2,857	3,105
Gross liabilities at end of period	78,041	71,997
Property and Casualty Insurance and Reinsurance, Excluding Retroactive Reinsurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses, current accident year events	31,777	31,179
Incurred losses and loss adjustment expenses, prior accident years' events	69	(396)
Total	31,846	30,783
Paid losses and loss adjustment expenses, current accident year events	(11,691)	(13,144)
Paid losses and loss adjustment expenses, prior accident years' events	(15,259)	(13,967)
Total	(26,950)	(27,111)
Foreign currency translation adjustment	$ 124	$ (178)

Unpaid losses and loss adjust_4

Unpaid losses and loss adjustment expenses - Narrative (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Primary Insurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses for (reductions of) prior years' accident events	$ (273)
Property and Casualty Reinsurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses for (reductions of) prior years' accident events	342
Property and Casualty Insurance and Reinsurance, Excluding Retroactive Reinsurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses for (reductions of) prior years' accident events	$ 69	$ (396)

Retroactive reinsurance contr_3

Retroactive reinsurance contracts - Reconciliation of changes in claim liabilities and deferred charge assets (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Unpaid losses and loss adjustment expenses, beginning of year	$ 42,441	$ 41,834
Unpaid losses and loss adjustment expenses, end of year	41,786	41,364
Deferred charges reinsurance assumed, beginning of year	(13,747)	(14,104)
Deferred charges reinsurance assumed, end of year	(13,012)	(13,359)
Retroactive Reinsurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses, prior accident years' events	866	825
Total incurred losses and loss adjustment expenses	866	918
Unpaid Losses and Loss Adjustment Expenses [Member] | Retroactive Reinsurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses, current accident year events		175
Incurred losses and loss adjustment expenses, prior accident years' events	131	(2)
Total incurred losses and loss adjustment expenses	131	173
Paid losses and loss adjustment expenses	(786)	(643)
Deferred Charges Reinsurance Assumed [Member] | Retroactive Reinsurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and loss adjustment expenses, current accident year events		(82)
Incurred losses and loss adjustment expenses, prior accident years' events	735	827
Total incurred losses and loss adjustment expenses	$ 735	$ 745

Retroactive reinsurance contr_4

Retroactive reinsurance contracts - Narrative (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Effects of Reinsurance [Line Items]
Unpaid losses and loss adjustment expenses under retroactive reinsurance contracts	$ 41,786	$ 41,364	$ 42,441	$ 41,834
Deferred charges under retroactive reinsurance contracts	13,012	13,359	13,747	$ 14,104
Retroactive Reinsurance [Member]
Effects of Reinsurance [Line Items]
Incurred losses and loss adjustment expenses, prior accident years' events	866	$ 825
NICO [Member] | AIG [Member] | Retroactive Reinsurance [Member]
Effects of Reinsurance [Line Items]
Maximum contractual liability under contract	20,000
Unpaid losses and loss adjustment expenses under retroactive reinsurance contracts	18,200		18,200
Deferred charges under retroactive reinsurance contracts	$ 5,800		$ 6,300

Notes payable and other borro_3

Notes payable and other borrowings (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2020EUR (€)	Sep. 30, 2020JPY (¥)	Sep. 30, 2020GBP (£)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings		€ 6,850	¥ 625.5	£ 1,750
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 68,800				$ 65,778
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	38,891				37,590
Insurance and Other [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Other borrowings	4,676				5,262
Short-term borrowings	$ 960				1,472
Weighted average interest rate, percentage	4.20%	4.20%	4.20%	4.20%
Short-term borrowings, weighted average interest rate	2.70%	2.70%	2.70%	2.70%
Insurance and Other [Member] | Berkshire Hathaway Inc. (Parent) [Member] | U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,320				8,324
Weighted average interest rate, percentage	3.20%	3.20%	3.20%	3.20%
Insurance and Other [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Euro Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,986				7,641
Weighted average interest rate, percentage	1.00%	1.00%	1.00%	1.00%
Insurance and Other [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 5,902				3,938
Weighted average interest rate, percentage	0.60%	0.60%	0.60%	0.60%
Insurance and Other [Member] | Minimum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] | Minimum [Member] | Berkshire Hathaway Inc. (Parent) [Member] | U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] | Minimum [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Euro Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2021
Insurance and Other [Member] | Minimum [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Insurance and Other [Member] | Maximum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Insurance and Other [Member] | Maximum [Member] | Berkshire Hathaway Inc. (Parent) [Member] | U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Insurance and Other [Member] | Maximum [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Euro Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2035
Insurance and Other [Member] | Maximum [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2060
Berkshire Hathaway Energy [Member] | Railroad, Utilities and Energy [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Senior unsecured debt	$ 11,462				8,581
Berkshire Hathaway Energy [Member] | Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2021
Berkshire Hathaway Energy [Member] | Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2050
Berkshire Hathaway Energy Subsidiaries | Railroad, Utilities and Energy [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 31,693				30,772
Weighted average interest rate, percentage	4.30%	4.30%	4.30%	4.30%
Berkshire Hathaway Energy Subsidiaries | Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Berkshire Hathaway Energy Subsidiaries | Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Burlington Northern Santa Fe And Subsidiaries | Railroad, Utilities and Energy [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,245				23,211
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Burlington Northern Santa Fe And Subsidiaries | Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Burlington Northern Santa Fe And Subsidiaries | Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2097
Berkshire Hathaway Finance Corporation [Member] | Insurance and Other [Member] | Subsidiaries [Member] | U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,829				8,679
Weighted average interest rate, percentage	4.10%	4.10%	4.10%	4.10%
Berkshire Hathaway Finance Corporation [Member] | Insurance and Other [Member] | Subsidiaries [Member] | Great Britain Pound Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,218				2,274
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Berkshire Hathaway Finance Corporation [Member] | Insurance and Other [Member] | Minimum [Member] | Subsidiaries [Member] | U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Berkshire Hathaway Finance Corporation [Member] | Insurance and Other [Member] | Minimum [Member] | Subsidiaries [Member] | Great Britain Pound Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Berkshire Hathaway Finance Corporation [Member] | Insurance and Other [Member] | Maximum [Member] | Subsidiaries [Member] | U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Berkshire Hathaway Finance Corporation [Member] | Insurance and Other [Member] | Maximum [Member] | Subsidiaries [Member] | Great Britain Pound Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2059
Berkshire Hathaway Energy and Subsidiaries [Member] | Railroad, Utilities and Energy [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 2,400				$ 3,214
Short-term borrowings, weighted average interest rate	1.80%	1.80%	1.80%	1.80%

Notes payable and other borro_4

Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	Oct. 29, 2020USD ($)	Oct. 31, 2020USD ($)	Apr. 30, 2020USD ($)	Apr. 30, 2020JPY (¥)	Mar. 31, 2020EUR (€)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020EUR (€)	Sep. 30, 2020JPY (¥)	Sep. 30, 2020GBP (£)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings										€ 6,850	¥ 625.5	£ 1,750
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings						$ 38,891		$ 38,891					$ 37,590
Insurance and Other [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation						$ 1,200		$ 1,200
Insurance and Other [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage						4.20%		4.20%		4.20%	4.20%	4.20%
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] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Gains (losses) attributable to changes in foreign currency exchange rates						$ (549)	$ 383	$ (447)	$ 447
Insurance and Other [Member] | Senior Notes [Member] | Subsidiaries [Member] | Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Repayments of borrowings								350
Insurance and Other [Member] | Senior Notes [Member] | Subsidiaries [Member] | Berkshire Hathaway Finance Corporation [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of borrowings		$ 550
Principal amount of debt issued		2,500
Insurance and Other [Member] | Senior Notes [Member] | Notes Due 2025 at 0.0% [Member] | Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings | €					€ 1,000
Principal amount of debt issued | €					€ 1,000
Debt instrument, interest rate, stated percentage					0.00%
Debt maturity year					2025
Insurance and Other [Member] | Senior Notes [Member] | Debt Due 2023 To 2060 [Member] | Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 1,800	¥ 195.5
Weighted average interest rate, percentage			1.07%	1.07%
Insurance and Other [Member] | Senior Notes [Member] | Debt Due 2023 To 2060 [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year			2023	2023
Insurance and Other [Member] | Senior Notes [Member] | Debt Due 2023 To 2060 [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year			2060	2060
Insurance and Other [Member] | Senior Notes [Member] | Notes Due 2030 at 1.85% [Member] | Subsidiaries [Member] | Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued								$ 500
Debt instrument, interest rate, stated percentage						1.85%		1.85%		1.85%	1.85%	1.85%
Debt maturity year								2030
Insurance and Other [Member] | Senior Notes [Member] | Notes Due 2030 at 1.45% [Member] | Subsidiaries [Member] | Berkshire Hathaway Finance Corporation [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		$ 750
Debt instrument, interest rate, stated percentage		1.45%
Debt maturity year		2030
Insurance and Other [Member] | Senior Notes [Member] | Notes Due 2050 at 2.85% [Member] | Subsidiaries [Member] | Berkshire Hathaway Finance Corporation [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		$ 1,750
Debt instrument, interest rate, stated percentage		2.85%
Debt maturity year		2050
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings						$ 68,800		$ 68,800					$ 65,778
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Repayments of borrowings								$ 1,900
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%	4.50%
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Minimum [Member] | Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year								2021
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Maximum [Member] | Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year								2050
Railroad, Utilities and Energy [Member] | Debt Due 2025 To 2062 [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued								$ 5,500
Weighted average interest rate, percentage						3.40%		3.40%		3.40%	3.40%	3.40%
Railroad, Utilities and Energy [Member] | Debt Due 2025 To 2062 [Member] | Subsidiaries [Member] | Minimum [Member] | Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year								2025
Railroad, Utilities and Energy [Member] | Debt Due 2025 To 2062 [Member] | Subsidiaries [Member] | Maximum [Member] | Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year								2062
Railroad, Utilities and Energy [Member] | Senior Notes [Member] | Notes Due 2031 at 1.65% [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 500
Debt instrument, interest rate, stated percentage	1.65%
Debt maturity year	2031
Railroad, Utilities and Energy [Member] | Senior Notes [Member] | Notes Due 2051 at 2.85% [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,500
Debt instrument, interest rate, stated percentage	2.85%
Debt maturity year	2051
Railroad, Utilities and Energy [Member] | Senior Unsecured Debenture [Member] | Debentures Due 2051 [Member] | Subsidiaries [Member] | BNSF [Member]
Debt Instrument [Line Items]
Repayments of borrowings								$ 541
Principal amount of debt issued			$ 575
Debt instrument, interest rate, stated percentage			3.05%	3.05%
Debt maturity year			2051	2051

Notes payable and other borro_5

Notes payable and other borrowings - Credit agreements - Narrative (Detail) - Line of Credit and Commercial Paper Facilities [Member] - Subsidiaries [Member] $ in Billions	Sep. 30, 2020USD ($)
Line of Credit Facility [Line Items]
Unused lines of credit available	$ 9.5
Berkshire Hathaway Energy and Subsidiaries [Member]
Line of Credit Facility [Line Items]
Unused lines of credit available	$ 7.8

Fair value measurements - Finan

Fair value measurements - Financial assets and liabilities (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions		Sep. 30, 2020USD ($)		Sep. 30, 2020EUR (€)	Sep. 30, 2020JPY (¥)	Sep. 30, 2020GBP (£)	Dec. 31, 2019USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		$ 19,435					$ 18,685
Investments in equity securities		245,317	[1]				248,027	[2]
Loans and finance receivables - carrying value		18,584					17,527
Notes payable and other borrowings - carrying value				€ 6,850	¥ 625.5	£ 1,750
Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings - carrying value		68,800					65,778
Insurance and Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		19,435					18,685
Investments in equity securities		245,317					248,027
Equity method investments - carrying value		17,152					17,505
Loans and finance receivables - carrying value		18,584					17,527
Derivative contract liabilities		1,547					968
Notes payable and other borrowings - carrying value		38,891					37,590
The Kraft Heinz Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments - carrying value		13,100					13,800
Equity method investments		9,700					10,500
U.S. Treasury, U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		3,377					3,090
Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		9,969					8,638
Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		5,574					6,352
Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		515					605
Fair Value, Measurements, Recurring [Member] | Quoted Prices (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in equity securities		236,804					237,271
Fair Value, Measurements, Recurring [Member] | Quoted Prices (Level 1) [Member] | The Kraft Heinz Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments		9,747					10,456
Fair Value, Measurements, Recurring [Member] | Quoted Prices (Level 1) [Member] | U.S. Treasury, U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		3,331					3,046
Fair Value, Measurements, Recurring [Member] | Quoted Prices (Level 1) [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		6,890					5,437
Fair Value, Measurements, Recurring [Member] | Quoted Prices (Level 1) [Member] | Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract assets	[3]	2
Fair Value, Measurements, Recurring [Member] | Quoted Prices (Level 1) [Member] | Accounts Payable, Accruals and Other Liabilities [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities	[3]	5					6
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in equity securities		38					46
Loans and finance receivables		2,509					1,809
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		84,315					76,237
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Insurance and Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		43,426					40,569
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury, U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		46					44
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		3,079					3,201
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		5,574					6,350
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		515					605
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract assets	[3]	64					23
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Accounts Payable, Accruals and Other Liabilities [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities	[3]	93					59
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in equity securities		8,475					10,710
Loans and finance receivables		17,228					16,052
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Insurance and Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		13					20
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Index Put Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities		1,547					968
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities							2
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract assets	[3]	195					122
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Accounts Payable, Accruals and Other Liabilities [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities	[3]	11					11
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in equity securities		245,317					248,027
Loans and finance receivables		18,584					17,527
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		68,800					65,778
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Insurance and Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		38,891					37,590
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Equity Index Put Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities		1,547					968
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | The Kraft Heinz Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments		13,101					13,757
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | U.S. Treasury, U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		3,377					3,090
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		9,969					8,638
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		5,574					6,352
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		515					605
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract assets	[3]	261					145
Fair Value, Measurements, Recurring [Member] | Carrying Value [Member] | Accounts Payable, Accruals and Other Liabilities [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities	[3]	109					76
Fair Value, Measurements, Recurring [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in equity securities		245,317					248,027
Loans and finance receivables		19,737					17,861
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		84,315					76,237
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Insurance and Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable and other borrowings		43,439					40,589
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Equity Index Put Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities		1,547					968
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | The Kraft Heinz Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments		9,747					10,456
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | U.S. Treasury, U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		3,377					3,090
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Foreign governments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		9,969					8,638
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		5,574					6,352
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in fixed maturity securities		515					605
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract assets	[3]	261					145
Fair Value, Measurements, Recurring [Member] | Fair Value [Member] | Accounts Payable, Accruals and Other Liabilities [Member] | Railroad, Utilities and Energy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative contract liabilities	[3]	$ 109					$ 76
[1]	Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion).
[2]	Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion).
[3]	Assets are included in other assets and liabilities are included in accounts payable, accruals and other liabilities.

Fair value measurements - Signi

Fair value measurements - Significant unobservable inputs (Detail) - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Net derivative contract liabilities - Beginning Balance	$ (857)	$ (2,343)
Net derivative contract liabilities - Gains (losses) included in earnings	(72)	1,528
Net derivative contract liabilities - Gains (losses) included in regulatory assets and liabilities	(36)	(41)
Net derivative contract liabilities - Acquisitions, dispositions and settlements	(398)	(282)
Net derivative contract liabilities - Ending Balance	(1,363)	(1,138)
Investments in Fixed Maturity and Equity Securities [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	10,407	7
Gains (losses) included in earnings	(2,235)	499
Acquisitions, dispositions and settlements	(2)	10,002
Ending Balance	$ 8,170	$ 10,508

Fair value measurements - Other

Fair value measurements - Other information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)		Dec. 31, 2019USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of investments	$ 245,317	[1]	$ 248,027	[2]
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of investments	8,475		$ 10,710
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member] | Option Pricing Model [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative contract liabilities, fair value	1,547
Significant Unobservable Inputs (Level 3) [Member] | Preferred Stock [Member] | Fair Value, Measurements, Recurring [Member] | Discounted Cash Flow [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of investments	8,159
Significant Unobservable Inputs (Level 3) [Member] | Common Stock Warrants [Member] | Fair Value, Measurements, Recurring [Member] | Warrant Pricing Model [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of investments	$ 10
Significant Unobservable Inputs (Level 3) [Member] | Expected Duration [Member] | Weighted Average [Member] | Preferred Stock [Member] | Fair Value, Measurements, Recurring [Member] | Discounted Cash Flow [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs, term	9 years
Significant Unobservable Inputs (Level 3) [Member] | Expected Duration [Member] | Weighted Average [Member] | Common Stock Warrants [Member] | Fair Value, Measurements, Recurring [Member] | Warrant Pricing Model [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs, term	9 years
Significant Unobservable Inputs (Level 3) [Member] | Discount for Transferability Restrictions and Subordination [Member] | Weighted Average [Member] | Preferred Stock [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs	0.0375
Significant Unobservable Inputs (Level 3) [Member] | Volatility [Member] | Weighted Average [Member] | Fair Value, Measurements, Recurring [Member] | Option Pricing Model [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs	0.20
Significant Unobservable Inputs (Level 3) [Member] | Volatility [Member] | Weighted Average [Member] | Common Stock Warrants [Member] | Fair Value, Measurements, Recurring [Member] | Warrant Pricing Model [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs	0.28
[1]	Approximately 70% of the aggregate fair value was concentrated in four companies (American Express Company – $15.2 billion; Apple Inc. – $111.7 billion; Bank of America Corporation – $24.9 billion and The Coca-Cola Company – $19.7 billion).
[2]	Approximately 60% of the aggregate fair value was concentrated in four companies (American Express Company – $18.9 billion; Apple Inc. – $73.7 billion; Bank of America Corporation – $33.4 billion and The Coca-Cola Company – $22.1 billion).

Common stock - Narrative (Detai

Common stock - Narrative (Detail)	9 Months Ended
	Sep. 30, 2020USD ($)Voteshares	Dec. 31, 2019shares
Class of Stock [Line Items]
Preferred Stock, shares authorized	1,000,000
Preferred Stock, shares issued	0
Economic equivalent of Class B share to Class A share	0.0667%
Common Stock Repurchase Program [Member]
Class of Stock [Line Items]
Shares repurchase, authorization description	Berkshire’s common stock repurchase program permits Berkshire to repurchase its Class A and Class B shares any time that Warren Buffett, Berkshire’s Chairman of the Board and Chief Executive Officer, and Charlie Munger, Vice Chairman of the Board, believe that the repurchase price is below Berkshire’s intrinsic value, conservatively determined.
Minimum cash, cash equivalents and U.S. Treasury Bills threshold after repurchase of common stock shares, amount | $	$ 20,000,000,000
Class A [Member]
Class of Stock [Line Items]
Number of votes entitled per share, number | Vote	1
Shares outstanding	650,946	701,970
Class B [Member]
Class of Stock [Line Items]
Number of votes entitled per share, number | Vote	0.0001
Number of shares of Class B stock obtainable from converting one Class A share	1,500
Shares outstanding	1,379,535,071	1,384,481,533
Equivalent Class A [Member]
Class of Stock [Line Items]
Shares outstanding	1,570,636	1,624,958

Common stock (Detail)

Common stock (Detail)	9 Months Ended
	Sep. 30, 2020shares
Class A [Member]
Class of Stock [Line Items]
Shares issued, beginning balance	719,307
Treasury shares, beginning balance	(17,337)
Shares outstanding, beginning balance	701,970
Conversions of Class A common stock to Class B common stock	(39,694)
Treasury stock acquired	(11,330)
Shares issued, ending balance	679,613
Treasury shares, ending balance	(28,667)
Shares outstanding, ending balance	650,946
Class B [Member]
Class of Stock [Line Items]
Shares issued, beginning balance	1,408,183,852
Treasury shares, beginning balance	(23,702,319)
Shares outstanding, beginning balance	1,384,481,533
Conversions of Class A common stock to Class B common stock	59,541,000
Treasury stock acquired	(64,487,462)
Shares issued, ending balance	1,467,724,852
Treasury shares, ending balance	(88,189,781)
Shares outstanding, ending balance	1,379,535,071

Common stock (Parenthetical) (D

Common stock (Parenthetical) (Detail)	Sep. 30, 2020$ / sharesshares
Class A [Member]
Class of Stock [Line Items]
Common Stock, par value per share | $ / shares	$ 5
Common Stock, shares authorized | shares	1,650,000
Class B [Member]
Class of Stock [Line Items]
Common Stock, par value per share | $ / shares	$ 0.0033
Common Stock, shares authorized | shares	3,225,000,000

Income taxes - Narrative (Detai

Income taxes - Narrative (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Effective income tax rate	19.80%	18.70%	30.80%	20.20%

Accumulated other comprehensi_3

Accumulated other comprehensive income (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	$ 424,791
Other comprehensive income, net	53	$ (393)
Balance at end of period	415,155
Unrealized appreciation of investments, net [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	481	370
Other comprehensive income, net	29	137
Balance at end of period	510	507
Foreign currency translation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	(4,346)	(4,603)
Other comprehensive income, net	(28)	(534)
Balance at end of period	(4,374)	(5,137)
Defined benefit pension plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	(1,369)	(816)
Other comprehensive income, net	67	33
Balance at end of period	(1,302)	(783)
Other AOCI transactions [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	(9)	34
Other comprehensive income, net	(15)	(29)
Balance at end of period	(24)	5
Accumulated other comprehensive income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	(5,243)	(5,015)
Balance at end of period	$ (5,190)	$ (5,408)

Supplemental cash flow inform_3

Supplemental cash flow information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for income taxes	$ 2,715	$ 4,395
Non-cash investing and financing activities:
Non-cash acquisition of equity securities	430
Insurance and Other [Member]
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for interest	892	879
Railroad, Utilities and Energy [Member]
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for interest	$ 2,174	$ 2,149

Contingencies and Commitments -

Contingencies and Commitments - Narrative (Detail) - Berkshire Hathaway Energy [Member] - Dominion Energy, Inc. [Member] $ in Billions	Oct. 05, 2020USD ($)	Jul. 31, 2020USD ($)Bcfemi	Sep. 30, 2020
Long Term Purchase Commitment [Line Items]
Business acquisition, contingent acquisition description			to acquire substantially all of Dominion’s natural gas transmission and storage business, which includes more than 7,700 miles of natural gas transmission pipelines, about 900 billion cubic feet of operated natural gas storage capacity and partial ownership of a liquefied natural gas export, import and storage facility.
Natural gas storage capacity acquired | Bcfe		900
Business combination, contingent consideration acquisition price		$ 4
Business acquisition, asset-related long-term debt		$ 5.7
First Acquisition Agreement [Member] | Subsequent Event [Member]
Long Term Purchase Commitment [Line Items]
Business acquisition, date of acquisition	Oct. 5, 2020
Payment for acquisition of business in cash	$ 2.7
Business acquisition assumed debt	$ 5.3
Business acquisition, date of completed	Nov. 1, 2020
Second Acquisition Agreement [Member] | Subsequent Event [Member]
Long Term Purchase Commitment [Line Items]
Business acquisition, date of acquisition	Oct. 5, 2020
Payment for acquisition of business in cash	$ 1.3
Business acquisition assumed debt	$ 0.4
Minimum [Member]
Long Term Purchase Commitment [Line Items]
Business acquisition, length of pipelines acquired | mi		7,700

Revenue from contracts with cus

Revenue from contracts with customers disaggregated by reportable segment and source of revenue (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 43,494	$ 45,169	$ 122,324	$ 132,021
Other revenues	19,530	19,803	58,805	57,227
Total revenues	63,024	64,972	181,129	189,248
Industrial and Commercial Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,943	6,390	15,782	19,444
Building Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,322	4,101	11,682	11,796
Consumer Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,036	3,528	10,373	10,487
Grocery and Convenience Store Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,905	8,298	23,051	24,375
Food and Beverage Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,968	4,202	11,561	12,648
Auto Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,195	2,250	5,999	6,312
Other Retail and Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,781	3,470	10,426	10,561
Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,988	8,717	22,260	25,069
Electricity and Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,356	4,213	11,190	11,329
Manufacturing Businesses [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	14,216	14,944	40,490	44,415
Other revenues	929	937	2,686	2,715
Total revenues	15,145	15,881	43,176	47,130
Manufacturing Businesses [Member] | Industrial and Commercial Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,889	6,346	15,639	19,308
Manufacturing Businesses [Member] | Building Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,322	4,101	11,682	11,796
Manufacturing Businesses [Member] | Consumer Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,036	3,528	10,373	10,487
Manufacturing Businesses [Member] | Other Retail and Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	599	524	1,691	1,602
Manufacturing Businesses [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	370	445	1,105	1,222
McLane Company [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	12,017	12,580	35,010	37,146
Other revenues	23	24	69	68
Total revenues	12,040	12,604	35,079	37,214
McLane Company [Member] | Grocery and Convenience Store Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,905	8,298	23,051	24,375
McLane Company [Member] | Food and Beverage Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,968	4,202	11,561	12,648
McLane Company [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	144	80	398	123
Service and Retailing Businesses [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,296	6,274	17,337	18,475
Other revenues	966	1,080	2,884	3,323
Total revenues	7,262	7,354	20,221	21,798
Service and Retailing Businesses [Member] | Industrial and Commercial Products [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	54	44	143	136
Service and Retailing Businesses [Member] | Auto Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,195	2,250	5,999	6,312
Service and Retailing Businesses [Member] | Other Retail and Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,182	2,946	8,735	8,959
Service and Retailing Businesses [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	865	1,034	2,460	3,068
BNSF [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,135	5,967	15,059	17,517
Other revenues	14	15	42	41
Total revenues	5,149	5,982	15,101	17,558
BNSF [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,135	5,967	15,059	17,517
Berkshire Hathaway Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,830	5,404	14,428	14,468
Other revenues	396	316	964	894
Total revenues	6,226	5,720	15,392	15,362
Berkshire Hathaway Energy [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,474	1,191	3,238	3,139
Berkshire Hathaway Energy [Member] | Electricity and Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,356	4,213	11,190	11,329
Insurance Corporate And Other [Member]
Disaggregation of Revenue [Line Items]
Other revenues	17,202	17,431	52,160	50,186
Total revenues	$ 17,202	$ 17,431	$ 52,160	$ 50,186

Revenue from contracts with c_2

Revenue from contracts with customers transaction price allocated to remaining performance obligations (Detail) $ in Millions	Sep. 30, 2020USD ($)
Electricity and Natural Gas [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 7,021
Electricity and Natural Gas [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 1,642
Performance obligations expected to be satisfied, period	1 year
Electricity and Natural Gas [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 5,379
Performance obligations expected to be satisfied, period
Other Sales and Service Contracts [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 3,663
Other Sales and Service Contracts [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 1,206
Performance obligations expected to be satisfied, period	1 year
Other Sales and Service Contracts [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 2,457
Performance obligations expected to be satisfied, period

Revenue from contracts with c_3

Revenue from contracts with customers transaction price allocated to remaining performance obligations (Detail 1) $ in Millions	Sep. 30, 2020USD ($)
Electricity and Natural Gas [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 7,021
Other Sales and Service Contracts [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction price allocated to remaining performance obligations	$ 3,663

Business segment data - Revenue

Business segment data - Revenues (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Total revenues	$ 63,024	$ 64,972	$ 181,129	$ 189,248
BNSF [Member]
Segment Reporting Information [Line Items]
Total revenues	5,149	5,982	15,101	17,558
Berkshire Hathaway Energy [Member]
Segment Reporting Information [Line Items]
Total revenues	6,226	5,720	15,392	15,362
Manufacturing Businesses [Member]
Segment Reporting Information [Line Items]
Total revenues	15,145	15,881	43,176	47,130
McLane Company [Member]
Segment Reporting Information [Line Items]
Total revenues	12,040	12,604	35,079	37,214
Service and Retailing Businesses [Member]
Segment Reporting Information [Line Items]
Total revenues	7,262	7,354	20,221	21,798
Operating Businesses [Member]
Segment Reporting Information [Line Items]
Total revenues	63,027	64,732	180,918	188,725
Operating Businesses [Member] | Insurance Group [Member]
Segment Reporting Information [Line Items]
Interest, dividend and other investment income	1,223	1,789	4,486	4,930
Total revenues	17,136	17,112	51,742	49,435
Operating Businesses [Member] | Insurance Group [Member] | GEICO [Member]
Segment Reporting Information [Line Items]
Premiums earned	8,540	8,996	26,689	26,487
Operating Businesses [Member] | Insurance Group [Member] | Berkshire Hathaway Reinsurance Group [Member]
Segment Reporting Information [Line Items]
Premiums earned	4,883	3,940	13,464	11,193
Operating Businesses [Member] | Insurance Group [Member] | Berkshire Hathaway Primary Group [Member]
Segment Reporting Information [Line Items]
Premiums earned	2,490	2,387	7,103	6,825
Operating Businesses [Member] | BNSF [Member]
Segment Reporting Information [Line Items]
Total revenues	5,176	6,021	15,195	17,676
Operating Businesses [Member] | Berkshire Hathaway Energy [Member]
Segment Reporting Information [Line Items]
Total revenues	6,226	5,720	15,392	15,362
Operating Businesses [Member] | Manufacturing Businesses [Member]
Segment Reporting Information [Line Items]
Total revenues	15,170	15,897	43,238	47,173
Operating Businesses [Member] | McLane Company [Member]
Segment Reporting Information [Line Items]
Total revenues	12,040	12,604	35,079	37,214
Operating Businesses [Member] | Service and Retailing Businesses [Member]
Segment Reporting Information [Line Items]
Total revenues	7,279	7,378	20,272	21,865
Corporate, Eliminations and Other [Member]
Segment Reporting Information [Line Items]
Total revenues	$ (3)	$ 240	$ 211	$ 523

Business segment data - Earning

Business segment data - Earnings (loss) before income taxes (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Investment and derivative contract gains/losses	$ 31,582	$ 10,926	$ 1,392	$ 41,296
Equity method earnings (losses)	290	644	333	936
Earnings (loss) before income taxes	37,930	20,489	10,290	65,895
Operating Businesses [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	6,958	8,538	20,348	23,443
Operating Businesses [Member] | Insurance Group [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	929	2,363	5,704	6,440
Operating Businesses [Member] | Insurance Group [Member] | Interest, Dividend and Other Investment Income [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	1,220	1,782	4,480	4,916
Operating Businesses [Member] | Insurance Group [Member] | GEICO [Member] | Insurance Premiums Earned [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	276	376	3,320	1,539
Operating Businesses [Member] | Insurance Group [Member] | Berkshire Hathaway Reinsurance Group [Member] | Insurance Premiums Earned [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	(441)	52	(2,033)	(305)
Operating Businesses [Member] | Insurance Group [Member] | Berkshire Hathaway Primary Group [Member] | Insurance Premiums Earned [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	(126)	153	(63)	290
Operating Businesses [Member] | BNSF [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	1,777	1,941	4,855	5,379
Operating Businesses [Member] | Berkshire Hathaway Energy [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	1,122	1,061	2,074	2,194
Operating Businesses [Member] | Manufacturing Businesses [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	2,255	2,484	5,765	7,205
Operating Businesses [Member] | McLane Company [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	96	50	205	220
Operating Businesses [Member] | Service and Retailing Businesses [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	779	639	1,745	2,005
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Investment and derivative contract gains/losses	31,582	10,926	1,392	41,296
Interest expense, not allocated to segments	(116)	(96)	(363)	(312)
Equity method earnings (losses)	290	644	333	936
Goodwill and intangible asset impairments	(25)		(10,659)
Corporate, Eliminations and Other [Member]
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes from operating businesses	$ (759)	$ 477	$ (761)	$ 532