Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings (Book Value And The Fair Value Of Long-Term Debt) (Details) (USD $)	Sep. 30, 2012	Dec. 31, 2011
Short-term Debt [Line Items]
Long-term Debt, Fair Value	$ 12,946,166,000	$ 12,176,251,000
Long-term Debt, Book Value	12,535,864,000	12,236,446,000
Notes payable to power authority	126,000,000	133,000,000
Entergy Arkansas [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,776,893,000	1,756,361,000
Long-term Debt, Book Value	1,870,076,000	1,875,921,000
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	1,670,740,000	1,642,388,000
Long-term Debt, Book Value	1,517,369,000	1,542,430,000
Entergy Louisiana [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	2,781,584,000	2,211,355,000
Long-term Debt, Book Value	2,639,714,000	2,252,312,000
Capital Lease Obligations	163,000,000	188,000,000
Entergy Mississippi [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	998,493,000	985,600,000
Long-term Debt, Book Value	920,484,000	920,439,000
Entergy New Orleans
Short-term Debt [Line Items]
Long-term Debt, Fair Value	172,182,000	169,270,000
Long-term Debt, Book Value	166,322,000	166,537,000
Entergy Texas [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	1,887,539,000	1,906,081,000
Long-term Debt, Book Value	1,628,270,000	1,677,127,000
System Energy [Member]
Short-term Debt [Line Items]
Long-term Debt, Fair Value	735,626,000	582,952,000
Long-term Debt, Book Value	853,771,000	747,048,000
Capital Lease Obligations	$ 139,000,000	$ 179,000,000