Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Effective Income Tax Rate [Line Items]
Effective income tax rate (in hundredths)	34.20%	33.10%	32.90%	34.40%
Capital Loss Carryforwards [Line Items]
Deferred tax asset					$ 2,700,000
Valuation allowance					1,200,000
Reversal of valuation allowance			1,200,000
Federal, net operating loss carryforwards	97,400,000		97,400,000
State, net operating loss carryforwards	90,000,000		90,000,000
Federal, operating loss carryfoward, expiration date			2031
State, operating loss carryforward, expiration date			2026
Uncertain Tax Positions [Abstract]
Interest associated with uncertain tax positions	43,900,000		43,900,000		41,000,000
Interest expense related to uncertain tax positions	1,300,000	2,100,000	2,900,000	4,000,000
Liability for unrecognized tax benefits [Roll Forward]
Balance at Period Start			102,785,000
Reduction for tax positions of current period			1,813,000
Additions for tax positions of prior periods			4,312,000
Reduction for tax positions of prior periods			876,000
Balance at Period End	104,408,000		104,408,000		102,785,000
Deposits with the IRS			8,200,000		52,200,000
Maximum increase (decrease) in unrecognized tax benefits as a result of settlement with the IRS	(73,300,000)		(73,300,000)
Amounts deposited with the IRS - accrued income taxes payable					45,900,000
Amounts deposited with the IRS- accrued interest payable					6,300,000
Cleco Power [Member]
Effective Income Tax Rate [Line Items]
Effective income tax rate (in hundredths)	30.80%	33.00%	31.50%	30.80%
Capital Loss Carryforwards [Line Items]
Deferred tax asset					2,700,000
Valuation allowance					1,200,000
Reversal of valuation allowance			1,200,000
Federal, net operating loss carryforwards	88,700,000		88,700,000
State, net operating loss carryforwards	81,300,000		81,300,000
Federal, operating loss carryfoward, expiration date			2031
State, operating loss carryforward, expiration date			2026
Uncertain Tax Positions [Abstract]
Interest associated with uncertain tax positions	17,000,000		17,000,000		15,200,000
Interest expense related to uncertain tax positions	900,000	1,300,000	1,800,000	2,500,000
Liability for unrecognized tax benefits [Roll Forward]
Balance at Period Start			60,975,000
Reduction for tax positions of current period			1,774,000
Balance at Period End	59,201,000		59,201,000
Maximum increase (decrease) in unrecognized tax benefits as a result of settlement with the IRS	$ (33,500,000)		$ (33,500,000)