Other Long-Term Liabilities Other Long-Term Liabilities (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Aug. 09, 2013	Sep. 30, 2012
Other Long-Term Liabilities
Interest rate swap liabilities	$ 1,199		$ 1,723
Environmental agreements liability	190		237
EnergyRight® financing obligation	149		148
Membership interests of VIE subject to mandatory redemption, amount, noncurrent	38		0
Coal contract derivative liabilities	35		205
Commodity swap derivative liabilities	36		59
Currency swap liabilities	15		54
Other	199		254
Total other long-term liabilities	1,861		2,680
Percentage of membership interests issued		100.00%
Membership interests of VIE subject to mandatory redemption	40	40	0
SCCG balloon payment		4
Membership interests of VIE subject to mandatory redemption, interest rate, stated percentage		7.00%
Membership interests of VIE subject to mandatory redemption, amount, current	2
Energy Right Program
Other Long-Term Liabilities
Number of days in default	180 days
Energy Right Solutions program obligation	186		185
Accounts payable and accrued liabilities \| Energy Right Program
Other Long-Term Liabilities
Energy Right Solutions program obligation	$ 37		$ 37

Carrying amount as of the balance sheet date of the liability arising from commodity contracts such as futures contracts tied to the movement of a particular commodity, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer.

No definition available.