Consolidated Balance Sheet (Supplemental) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Sep. 30, 2012	Mar. 31, 2012
Statement of Financial Position [Abstract]
Variable Interest Entities Assets Liabilities	The following table presents the assets and liabilities of our consolidated variable interest entities. The assets of any variable interest entity can only be used to settle obligations of that respective variable interest entity, and the creditors (or beneficial interest holders) do not have recourse to us or to our other assets. These assets and liabilities are included in the consolidated balance sheet above.
ASSETS
Finance receivables, net	$ 61,090	$ 58,042
Investments in operating leases, net	19,561	18,743
Other Assets	1,535	1,727
Total assets	93,128	88,913
LIABILITIES
Debt	76,674	73,234
Other liabilities	2,759	2,605
Total liabilities	85,359	81,251
Variable Interest Entity, Primary Beneficiary [Member]
ASSETS
Finance receivables, net	10,176	10,527	[1]
Investments in operating leases, net	593	0	[1]
Other Assets	6	3	[1]
Total assets	10,775	10,530	[1]
LIABILITIES
Debt	9,336	9,789
Other liabilities	2	2
Total liabilities	$ 9,338	$ 9,791

[1]  Certain prior period amounts have been reclassified to conform to the current period presentation.