Condensed Financial Information - Statements of Cash Flows (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net earnings attributable to Berkshire Hathaway shareholders	$ 19,476	$ 14,824	$ 10,254
Adjustments to reconcile net earnings to cash flows from operating activities:
Income taxes payable	3,514	1,710	1,493
Other noncash adjustments	(373)	213	(2)
Net cash flows from operating activities	27,704	20,950	20,476
Cash flows from investing activities:
Sales of fixed maturity securities	4,311	2,982	3,353
Net cash flows from investing activities	(27,535)	(10,574)	(19,189)
Cash flows from financing activities:
Other financing activities	(134)	48	18
Net cash flows from financing activities	961	(806)	(2,217)
Increase (decrease) in cash and cash equivalents	1,194	9,693	(928)
Cash and cash equivalents at beginning of year	46,992	37,299	38,227
Cash and cash equivalents at end of year	48,186	46,992	37,299
Other cash flow information:
Income taxes paid	5,401	4,695	2,885
Berkshire Hathaway (Parent) [Member]
Cash flows from operating activities:
Net earnings attributable to Berkshire Hathaway shareholders	19,476	14,824	10,254
Adjustments to reconcile net earnings to cash flows from operating activities:
Undistributed earnings of subsidiaries	(13,657)	(8,301)	(4,546)
Income taxes payable	396	80	69
Other noncash adjustments	112	101	70
Net cash flows from operating activities	6,327	6,704	5,847
Cash flows from investing activities:
Investments in H.J. Heinz Holding Corporation	(12,250)
Sales of fixed maturity securities			298
Investments in and advances to subsidiaries	(433)	(1,525)	(3,633)
Net cash flows from investing activities	(12,683)	(1,525)	(3,335)
Cash flows from financing activities:
Proceeds from borrowings	2,611	1,740	2,021
Repayments of borrowings	(2,656)	(1,751)	(2,094)
Acquisitions of noncontrolling interests	(836)	(800)	(1,811)
Acquisitions of treasury stock		(1,296)	(67)
Other financing activities	92	196	112
Net cash flows from financing activities	(789)	(1,911)	(1,839)
Increase (decrease) in cash and cash equivalents	(7,145)	3,268	673
Cash and cash equivalents at beginning of year	10,557	7,289	6,616
Cash and cash equivalents at end of year	3,412	10,557	7,289
Other cash flow information:
Income taxes paid	4,080	3,406	1,882
Interest paid	$ 205	$ 180	$ 122