Consolidated Statements of Earnings - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Revenues:
Sales and service revenues		$ 41,452	$ 42,392
Leasing revenues		1,428	1,436
Total revenues		61,265	60,678
Investment and derivative contract gains (losses)		(70,275)	20,322
Costs and expenses:
Total costs and expenses		54,339	53,521
Earnings (loss) before income taxes and equity method earnings		(63,349)	27,479
Equity method earnings		300	168
Earnings (loss) before income taxes		(63,049)	27,647
Income tax expense (benefit)		(13,352)	5,915
Net earnings (loss)		(49,697)	21,732
Earnings attributable to noncontrolling interests		49	71
Net earnings (loss) attributable to Berkshire Hathaway shareholders		$ (49,746)	$ 21,661
Equivalent Class A [Member]
Costs and expenses:
Net earnings (loss) per average equivalent share		$ (30,653)	$ 13,209
Average equivalent shares outstanding		1,622,889	1,639,821
Equivalent Class B [Member]
Costs and expenses:
Net earnings (loss) per average equivalent share	[1]	$ (20.44)	$ 8.81
Average equivalent shares outstanding		2,434,333,367	2,459,731,886
Insurance and Other [Member]
Revenues:
Insurance premiums earned		$ 15,748	$ 14,319
Sales and service revenues		31,926	32,409
Leasing revenues		1,428	1,436
Interest, dividend and other investment income		2,276	2,117
Total revenues		51,378	50,281
Costs and expenses:
Insurance losses and loss adjustment expenses		10,979	10,174
Life, annuity and health insurance benefits		1,383	904
Insurance underwriting expenses		2,924	2,756
Cost of sales and services		25,392	25,767
Cost of leasing		1,002	1,020
Selling, general and administrative expenses		4,471	4,432
Interest expense		296	262
Total costs and expenses		46,447	45,315
Freight Rail Transportation [Member]
Revenues:
Total revenues		5,380	5,725
Costs and expenses:
Expenses		3,593	3,982
Utilities and Energy [Member]
Revenues:
Sales and service revenues		3,634	3,825
Costs and expenses:
Cost of sales and other expenses		2,722	2,842
Railroad, Utilities and Energy [Member]
Revenues:
Service revenues and other income		873	847
Total revenues		9,887	10,397
Costs and expenses:
Other expenses		849	653
Interest expense		728	729
Total costs and expenses		$ 7,892	$ 8,206

[1] Class B shares are economically equivalent to one-fifteen-hundredth of a Class A share. Accordingly, net earnings per average equivalent Class B share outstanding is equal to one-fifteen-hundredth of the equivalent Class A amount. See Note 18.