Customer Financing (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Customer Financing [Line Items]
Customer financing receivables individually evaluated for impairment	$ 91	$ 95
Impaired customer financing receivables	$ 0	$ 0
B Credit Rating [Member]
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	17.00%
B B B Credit Rating [Member]
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	2.00%