Debt, Other Financing Obligations and Other Credit Facilities (Table 1) (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Summary of total financing obligations
Short-term financing obligations, including current maturities	$ 350	$ 489
Long-term financing obligations	12,531	13,517
Total	$ 12,881	$ 14,006