Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
ASSETS
Cash and cash equivalents	$ 46,992	$ 37,299
Investments in equity securities	87,662	76,991
Inventories	9,675	8,975
Goodwill	54,523	53,213
Total assets	427,452	392,647
LIABILITIES
Income taxes, principally deferred	44,494	37,804
Total liabilities	235,864	223,686
SHAREHOLDERS' EQUITY
Common stock	8	8
Capital in excess of par value	37,230	37,807
Accumulated other comprehensive income	27,500	17,654
Retained earnings	124,272	109,448
Treasury stock, at cost	(1,363)	(67)
Berkshire Hathaway shareholders' equity	187,647	164,850
Noncontrolling interests	3,941	4,111
Total shareholders' equity	191,588	168,961
Total liabilities and shareholders' equity	427,452	392,647
Insurance and Other [Member]
ASSETS
Cash and cash equivalents	42,358	33,513
Investments in fixed maturity securities	31,449	31,222
Investments in equity securities	86,467	76,063
Other investments	16,057	13,111
Receivables	21,753	19,012
Inventories	9,675	8,975
Property, plant and equipment	19,188	18,177
Goodwill	33,274	32,125
Other	17,875	18,121
Total assets	278,096	250,319
LIABILITIES
Losses and loss adjustment expenses	64,160	63,819
Unearned premiums	10,237	8,910
Life, annuity and health insurance benefits	10,943	9,924
Accounts payable, accruals and other liabilities	21,149	18,466
Notes payable and other borrowings	13,535	13,768
Total liabilities	120,024	114,887
Railroad, Utilities and Energy [Member]
ASSETS
Cash and cash equivalents	2,570	2,246
Property, plant and equipment	87,684	82,214
Goodwill	20,213	20,056
Other	13,441	12,861
Total assets	123,908	117,377
LIABILITIES
Accounts payable, accruals and other liabilities	13,113	13,016
Notes payable and other borrowings	36,156	32,580
Total liabilities	49,269	45,596
Finance and Financial Products [Member]
ASSETS
Cash and cash equivalents	2,064	1,540
Investments in fixed maturity securities	842	966
Other investments	4,952	3,810
Loans and finance receivables	12,809	13,934
Goodwill	1,036	1,032
Other	3,745	3,669
Total assets	25,448	24,951
LIABILITIES
Accounts payable, accruals and other liabilities	1,099	1,224
Derivative contract liabilities	7,933	10,139
Notes payable and other borrowings	13,045	14,036
Total liabilities	$ 22,077	$ 25,399