Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings (Book Value And The Fair Value Of Long-Term Debt) (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Short-term Debt [Line Items]
Long-term Debt, Fair Value	$ 12,866,746,000	$ 12,849,330,000
Long-term Debt, Book Value	12,359,756,000	12,638,834,000
Notes payable to power authority	110,000,000	110,000,000
Entergy Arkansas [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	2,020,198,000	1,876,335,000
Long-term Debt, Book Value	2,123,945,000	2,123,895,000
Long term DOE obligations	181,000,000	181,000,000
Entergy Gulf States Louisiana [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,805,683,000	1,668,819,000
Long-term Debt, Book Value	1,637,489,000	1,517,429,000
Entergy Louisiana [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	2,913,342,000	2,921,322,000
Long-term Debt, Book Value	2,813,918,000	2,826,095,000
Capital Lease Obligations	151,000,000	163,000,000
Entergy Mississippi [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,211,692,000	1,230,714,000
Long-term Debt, Book Value	1,139,556,000	1,169,519,000
Entergy New Orleans
Short-term Debt [Line Items]
Long-term Debt, Fair Value	225,865,000	200,725,000
Long-term Debt, Book Value	221,302,000	196,300,000
Entergy Texas [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,833,724,000	1,885,672,000
Long-term Debt, Book Value	1,595,957,000	1,617,813,000
System Energy [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	667,758,000	664,670,000
Long-term Debt, Book Value	742,926,000	783,799,000
Capital Lease Obligations	$ 98,000,000	$ 139,000,000