Customer Financing (Financing Receivable Credit Quality Indicators) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	$ 2,289	$ 1,876
BBB Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	1,324	973
BB Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	538	536
B Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	383	258
CCC Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	44	23
Other Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables		$ 86