Condensed Financial Information - Statements of Cash Flows (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net earnings (loss) attributable to Berkshire Hathaway shareholders	$ 96,223	$ (22,759)	$ 89,937
Adjustments to reconcile net earnings (loss) to operating cash flows:
Investment (gains) losses	(74,855)	67,623	(77,576)
Income taxes payable	14,865	(12,872)	15,330
Other	(6,023)	(4,206)	(3,382)
Net cash flows from operating activities	49,196	37,350	39,427
Cash flows from investing activities:
Other	685	239	770
Net cash flows from investing activities	(32,663)	(87,601)	29,392
Cash flows from financing activities:
Acquisitions of treasury stock	(9,171)	(7,854)	(27,061)
Other	(4,147)	(1,979)	(695)
Net cash flows from financing activities	(14,405)	(1,662)	(28,508)
Increase (decrease) in cash and cash equivalents and restricted cash	2,244	(52,307)	40,310
Other cash flow information:
Income taxes paid	7,765	4,236	5,412
Berkshire Hathaway Inc. (Parent) [Member]
Cash flows from operating activities:
Net earnings (loss) attributable to Berkshire Hathaway shareholders	96,223	(22,759)	89,937
Adjustments to reconcile net earnings (loss) to operating cash flows:
Investment (gains) losses	7	34	(35)
Undistributed (earnings) losses of consolidated subsidiaries	(85,550)	39,579	(74,961)
Non-cash dividends from subsidiaries	(1,811)	(7,220)	(2,126)
Income taxes payable	(44)	661	(389)
Other	(1,214)	(1,833)	(1,038)
Net cash flows from operating activities	7,611	8,462	11,388
Cash flows from investing activities:
Investments in and advances to consolidated subsidiaries, net	2,649	(11,852)	(174)
Purchases of U.S. Treasury Bills	(27,278)	(44,187)	(34,988)
Sales and maturities of U.S. Treasury Bills	31,234	37,915	57,296
Other		128
Net cash flows from investing activities	6,605	(17,996)	22,134
Cash flows from financing activities:
Proceeds from borrowings	2,054	1,970	2,174
Repayments of borrowings	(4,310)	(602)	(2,167)
Acquisitions of treasury stock	(9,171)	(7,854)	(27,061)
Net cash flows from financing activities	(11,427)	(6,486)	(27,054)
Increase (decrease) in cash and cash equivalents and restricted cash	2,789	(16,020)	6,468
Cash and cash equivalents at the beginning of the year	2,777	18,797	12,329
Cash and cash equivalents at the end of the year	5,566	2,777	18,797
Other cash flow information:
Income taxes paid	5,630	2,259	3,403
Interest paid	$ 297	$ 332	$ 377