Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings (Book Value And The Fair Value Of Long-Term Debt) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Short-term Debt [Line Items]
Long-term Debt, Fair Value	$ 12,849,330	$ 12,176,251
Entergy Arkansas [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,876,335	1,756,361
Entergy Gulf States Louisiana [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,668,819	1,642,388
Entergy Louisiana [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	2,921,322	2,211,355
Entergy Mississippi [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,230,714	985,600
Entergy New Orleans [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	200,725	169,270
Entergy Texas [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,885,672	1,906,081
System Energy [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	$ 664,670	$ 582,952