Summary of Significant Accounting Policies, Property, Plant and Equipment (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Property, Plant and Equipment [Abstract]
Unamortized computer software costs	$ 3,300,000	$ 3,800,000
Amortization of capitalized computer software costs	1,500,000	1,700,000	1,500,000
Useful lives of property, plant and equipment [Abstract]
Utility plant (in years)	5-58
Other (in years)	5-44
Property, plant and equipment consist of:
Regulated utility plants	3,759,541,000	3,552,054,000
Other	264,114,000	258,842,000
Property, plant and equipment	4,023,655,000	3,810,896,000
Accumulated depreciation	(1,230,783,000)	(1,162,456,000)
Net property, plant and equipment	2,792,872,000	2,648,440,000
Teche [Member]
Useful lives of property, plant and equipment [Abstract]
Utility plant (in years)	23
Cleco Power [Member]
Property, Plant and Equipment [Abstract]
Annual depreciation provisions expressed as a percentage of average depreciable property (in hundredths)	2.80%	2.55%	3.22%
Increase in the percentage of average depreciable property	0.25%
Property, plant and equipment consist of:
Property, plant and equipment	3,759,541,000	3,552,779,000
Accumulated depreciation	(1,153,004,000)	(1,085,945,000)
Net property, plant and equipment	$ 2,606,537,000	$ 2,466,834,000