Assets and Liabilities of Businesses Held For Sale and Discontinued Operations (Held for Sale Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended					3 Months Ended				9 Months Ended	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Discontinued Operation Or Asset Disposal Component [Member]	Dec. 31, 2011 Discontinued Operation Or Asset Disposal Component [Member]	Mar. 31, 2011 Consumer RV Marine [Member]	Jun. 30, 2011 Consumer Mexico [Member]	Jun. 30, 2011 Consumer Singapore [Member]	Sep. 30, 2011 Australian Home Lending [Member]	Sep. 30, 2012 South Korea CLL [Member]	Dec. 31, 2012 Business Property [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of NBCU	$ 227	$ 8,950	$ 2,510
Deferred Tax Liabilities, Net	5,871	7,052
Deferred income taxes				374	207
Assets held for sale	211	711
Liabilities of businesses held for sale	157	345
Property, plant and equipment - net	53,673	51,419
Other assets, all	62,217	75,612
Accounts Payable, Current	6,277	7,239
Other Liabilities	16,050	17,334
Consideration Received For Sale Of Business						$ 2,365	$ 1,943	$ 319	$ 4,577	$ 168	$ 2,406