Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 42,079	$ 46,992
Investments in equity securities	106,765	87,662
Inventories	9,880	9,675
Goodwill	54,735	54,523
Total assets	458,081	427,452
LIABILITIES
Income taxes, principally deferred	50,849	44,494
Total liabilities	246,650	235,864
SHAREHOLDERS' EQUITY
Common stock	8	8
Capital in excess of par value	36,082	37,230
Accumulated other comprehensive income	34,897	27,500
Retained earnings	138,758	124,272
Treasury stock, at cost	(1,363)	(1,363)
Berkshire Hathaway shareholders' equity	208,382	187,647
Noncontrolling interests	3,049	3,941
Total shareholders' equity	211,431	191,588
Total liabilities and shareholders' equity	458,081	427,452
Insurance and Other [Member]
ASSETS
Cash and cash equivalents	35,337	42,358
Investments in fixed maturity securities	28,872	31,449
Investments in equity securities	104,893	86,467
Other investments	23,732	16,057
Receivables	27,145	21,753
Inventories	9,880	9,675
Property, plant and equipment	19,461	19,188
Goodwill	33,356	33,274
Other	19,016	17,875
Total assets	301,692	278,096
LIABILITIES
Losses and loss adjustment expenses	64,818	64,160
Unearned premiums	11,670	10,237
Life, annuity and health insurance benefits	11,326	10,943
Accounts payable, accruals and other liabilities	21,755	21,149
Notes payable and other borrowings	13,023	13,535
Total liabilities	122,592	120,024
Railroad, Utilities and Energy [Member]
ASSETS
Cash and cash equivalents	4,691	2,570
Property, plant and equipment	91,095	87,684
Goodwill	20,343	20,213
Other	14,450	13,441
Total assets	130,579	123,908
LIABILITIES
Accounts payable, accruals and other liabilities	13,533	13,113
Notes payable and other borrowings	40,016	36,156
Total liabilities	53,549	49,269
Finance and Financial Products [Member]
ASSETS
Cash and cash equivalents	2,051	2,064
Investments in fixed maturity securities	663	842
Other investments	5,275	4,952
Loans and finance receivables	12,838	12,809
Goodwill	1,036	1,036
Other	3,947	3,745
Total assets	25,810	25,448
LIABILITIES
Accounts payable, accruals and other liabilities	1,103	1,099
Derivative contract liabilities	5,847	7,933
Notes payable and other borrowings	12,710	13,045
Total liabilities	$ 19,660	$ 22,077