Income Taxes, Effective Tax Rate Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income tax reconciliation [Abstract]
Income before tax	$ 228,975	$ 298,745	$ 397,889
Statutory rate (in hundredths)	35.00%	35.00%	35.00%
Tax at federal statutory rate	80,141	104,561	139,261
Increase (decrease):
Plant differences, including AFUDC flowthrough	(1,222)	(1,758)	(7,757)
Amortization of investment tax credits	(1,180)	(1,238)	(1,285)
State income taxes	(218)	2,155	11,897
Tax settlement	0	10,782	0
Other	(2,933)	(6,908)	382
Total taxes	65,327	102,897	142,498
Effective Rate (in hundredths)	28.50%	34.40%	35.80%
Cleco Power [Member]
Income tax reconciliation [Abstract]
Income before tax	214,981	212,244	222,512
Statutory rate (in hundredths)	35.00%	35.00%	35.00%
Tax at federal statutory rate	75,243	74,285	77,879
Increase (decrease):
Plant differences, including AFUDC flowthrough	(1,222)	(1,758)	(7,757)
Amortization of investment tax credits	(1,180)	(1,238)	(1,285)
State income taxes	(705)	(853)	5,798
Other	(4,003)	(1,027)	472
Total taxes	68,133	69,409	75,107
Effective Rate (in hundredths)	31.70%	32.70%	33.80%
New Markets Tax Credit [Member]
Increase (decrease):
New Markets Tax Credits	$ (9,261)	$ (4,697)	$ 0

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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 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 other 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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