Income Taxes, Effective Tax Rate Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income tax reconciliation [Abstract]
Income before tax	$ 221,855	$ 240,260	$ 228,975
Statutory rate (in hundredths)	35.00%	35.00%	35.00%
Tax at federal statutory rate	77,649	84,091	80,141
Increase (decrease):
Plant differences, including AFUDC flowthrough	462	427	(1,222)
Amortization of investment tax credits	(983)	(1,108)	(1,180)
State income taxes	23	1,094	(218)
Settlement with taxing authorities	(9,106)	0	0
New markets tax credits	(754)	(4,806)	(9,261)
Other	(175)	(123)	(2,933)
Total taxes	67,116us-gaap_IncomeTaxExpenseBenefit	79,575us-gaap_IncomeTaxExpenseBenefit	65,327us-gaap_IncomeTaxExpenseBenefit
Effective Rate (in hundredths)	30.30%	33.10%	28.50%
Cleco Power [Member]
Income tax reconciliation [Abstract]
Income before tax	231,290	229,791	214,981
Statutory rate (in hundredths)	35.00%	35.00%	35.00%
Tax at federal statutory rate	80,952	80,427	75,243
Increase (decrease):
Plant differences, including AFUDC flowthrough	462	427	(1,222)
Amortization of investment tax credits	(983)	(1,108)	(1,180)
State income taxes	351	730	(705)
Settlement with taxing authorities	(2,320)	0	0
Other	(1,488)	(1,095)	(4,003)
Total taxes	$ 76,974	$ 79,381	$ 68,133
Effective Rate (in hundredths)	33.30%	34.50%	31.70%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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