Pension Plan and Employee Benefits, Benefit Obligation, Plan Assets, and Funded Status (Details) (USD $)	1 Months Ended	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
General information		Benefits under the plan reflect an employee’s years of service, age at retirement, and highest total average compensation for any consecutive five calendar years during the last 10 years of employment with Cleco.
Discretionary contributions to pension plan	$ 60,000,000
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year		330,342,000		295,528,000
Service cost		8,390,000		7,451,000		7,010,000
Interest cost		17,629,000		17,145,000		16,454,000
Plan participants' contributions		0		0
Actuarial loss		19,452,000		23,540,000
Expenses paid		(1,208,000)		(1,262,000)
Medicare D		0		0
Benefits paid		(12,619,000)		(12,060,000)
Benefit obligation at end of year	361,986,000	361,986,000		330,342,000		295,528,000
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year		242,513,000		221,067,000
Actual return on plan assets		23,709,000		29,768,000
Employer contributions		60,000,000		5,000,000
Expenses paid		(1,208,000)		(1,262,000)
Benefits paid		(12,619,000)		(12,060,000)
Fair value of plan assets at end of year	312,395,000	312,395,000		242,513,000		221,067,000
Unfunded status	(49,591,000)	(49,591,000)		(87,829,000)
Pension Benefits [Member] | Current Plan Year [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions designated for current plan year	19,900,000
Pension Benefits [Member] | Prior Plan Year [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions designated for prior plan year	40,100,000
Other Benefits [Member]
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year		41,444,000		39,209,000
Service cost		1,532,000		1,511,000		1,414,000
Interest cost		1,818,000		1,965,000		2,140,000
Plan participants' contributions		1,251,000		1,176,000
Actuarial loss		141,000		1,231,000
Expenses paid		0		0
Other adjustments		452,000	[1]
Medicare D		206,000		424,000	[2]
Benefits paid		(4,164,000)		(4,072,000)
Benefit obligation at end of year	42,680,000	42,680,000		41,444,000		39,209,000
Change in plan assets [Roll Forward]
Expenses paid		0		0
Benefits paid		(4,164,000)		(4,072,000)
Unfunded status	(42,680,000)	(42,680,000)		(41,444,000)
Other Benefits [Member] | 2009 Plan Year [Member]
Change in benefit obligation [Roll Forward]
Medicare D				200,000
SERP Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
General information		Benefits under the plan reflect an employee’s years of service, age at retirement, and the sum of the highest base salary paid out of the last five calendar years and the average of the three highest bonuses paid during the 60 months prior to retirement, reduced by benefits received from any other defined benefit pension plan, SERP Plan or Cleco contributions under the enhanced 401(k) Plan to the extent such contributions exceed the limits of the 401(k) Plan.
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year		42,160,000		37,227,000
Service cost		1,566,000		1,531,000		1,608,000
Interest cost		2,105,000		2,122,000		2,015,000
Actuarial loss		2,529,000		2,878,000
Benefits paid		(2,096,000)		(1,598,000)
Benefit obligation at end of year	46,264,000	46,264,000		42,160,000		37,227,000
Change in plan assets [Roll Forward]
Benefits paid		$ (2,096,000)		$ (1,598,000)

[1] During 2011, Cleco received $0.5 million for the Early Retiree Reinsurance Program.

[2] Medicare D reimbursement of $0.2 million was related to the 2009 Plan year. (2) During 2011, Cleco received $0.5 million for the Early Retiree Reinsurance Program.