Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 35,695	$ 46,992
Investments in equity securities	103,274	87,662
Inventories	9,877	9,675
Goodwill	54,372	54,523
Total assets	446,563	427,452
LIABILITIES
Income taxes, principally deferred	49,547	44,494
Total liabilities	241,575	235,864
SHAREHOLDERS' EQUITY
Common stock	8	8
Capital in excess of par value	36,101	37,230
Accumulated other comprehensive income	33,565	27,500
Retained earnings	133,705	124,272
Treasury stock, at cost	(1,363)	(1,363)
Berkshire Hathaway shareholders' equity	202,016	187,647
Noncontrolling interests	2,972	3,941
Total shareholders' equity	204,988	191,588
Total liabilities and shareholders' equity	446,563	427,452
Insurance and Other [Member]
ASSETS
Cash and cash equivalents	31,216	42,358
Investments in fixed maturity securities	28,756	31,449
Investments in equity securities	101,933	86,467
Other investments	29,484	16,057
Receivables	21,956	21,753
Inventories	9,877	9,675
Property, plant and equipment	19,150	19,188
Goodwill	33,178	33,274
Other	18,982	17,875
Total assets	294,532	278,096
LIABILITIES
Losses and loss adjustment expenses	64,423	64,160
Unearned premiums	11,360	10,237
Life, annuity and health insurance benefits	10,520	10,943
Accounts payable, accruals and other liabilities	21,278	21,149
Notes payable and other borrowings	13,261	13,535
Total liabilities	120,842	120,024
Railroad, Utilities and Energy [Member]
ASSETS
Cash and cash equivalents	2,564	2,570
Property, plant and equipment	89,199	87,684
Goodwill	20,158	20,213
Other	14,696	13,441
Total assets	126,617	123,908
LIABILITIES
Accounts payable, accruals and other liabilities	13,186	13,113
Notes payable and other borrowings	37,861	36,156
Total liabilities	51,047	49,269
Finance and Financial Products [Member]
ASSETS
Cash and cash equivalents	1,915	2,064
Investments in fixed maturity securities	749	842
Other investments	5,235	4,952
Loans and finance receivables	12,855	12,809
Goodwill	1,036	1,036
Other	3,624	3,745
Total assets	25,414	25,448
LIABILITIES
Accounts payable, accruals and other liabilities	1,067	1,099
Derivative contract liabilities	6,241	7,933
Notes payable and other borrowings	12,831	13,045
Total liabilities	$ 20,139	$ 22,077