Finance Receivables Finance Receivables - Non-Accrual Status (Details) (Financial Services [Member], USD $) In Millions, unless otherwise specified					9 Months Ended
	Sep. 30, 2012 Consumer [Member]	Dec. 31, 2011 Consumer [Member]	Sep. 30, 2012 Non-consumer [Member]	Dec. 31, 2011 Non-consumer [Member]	Sep. 30, 2012 Minimum [Member]	Sep. 30, 2012 Minimum [Member] Finance Receivables [Member] Consumer [Member]
Financing Receivables [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 323	$ 402	$ 28	$ 27
Financing Receivable, Recorded Investment, Nonaccrual Status, Percentage of Receivable	0.70%	0.90%	0.10%	0.10%
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	$ 15	$ 14	$ 14
Number Of Days At Which Finance Receivables Are Put In Non Accrual Status						120 days
Number Of Days At Which Finance Receivables Are In Process Of Collection					90 days