Customer Financing (Allowance For Losses On Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance - January 1	$ (60)	$ (70)	$ (353)
Write-offs	11	10	269
Write-offs			14
Ending balance - December 31	(49)	(60)	(70)
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	$ (49)	$ (60)	$ (70)