Income Taxes, Effective Tax Rate Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income tax reconciliation [Abstract]
Income before tax	$ 298,745	$ 397,889	$ 115,886
Statutory rate (in hundredths)	35.00%	35.00%	35.00%
Tax at federal statutory rate	104,561	139,261	40,560
Increase (decrease):
Plant differences, including AFUDC flowthrough	(1,758)	(7,757)	(30,212)
Amortization of investment tax credits	(1,238)	(1,285)	(1,332)
State tax expense	2,155	11,897	4,763
Audit settlement	10,782	0	0
Other	(11,605)	382	(4,200)
Total taxes	102,897	142,498	9,579
Effective Rate (in hundredths)	34.40%	35.80%	8.30%
Cleco Power [Member]
Income tax reconciliation [Abstract]
Income before tax	212,244	222,512	126,463
Statutory rate (in hundredths)	35.00%	35.00%	35.00%
Tax at federal statutory rate	74,285	77,879	44,262
Increase (decrease):
Plant differences, including AFUDC flowthrough	(1,758)	(7,757)	(30,212)
Amortization of investment tax credits	(1,238)	(1,285)	(1,332)
State tax expense	(853)	5,798	5,131
Other	(1,027)	472	(2,552)
Total taxes	$ 69,409	$ 75,107	$ 15,297
Effective Rate (in hundredths)	32.70%	33.80%	12.10%

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The sum of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to the different depreciation and amortization methods allowed under generally accepted accounting principles and enacted tax laws.

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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to investment tax credits generated or utilized under enacted tax laws during the period.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to all income tax settlements for the period.

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