Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, Disclosures about Guarantees (Details) (USD $)								3 Months Ended				3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Feb. 28, 2010 Guarantee Issued to Cleco Power on behalf of Acadia [Member]	Mar. 31, 2013 Cleco Corporation [Member] Guarantee Issued to Entergy Louisiana and Entergy Gulf States for Performance Obligations of Perryville [Member]	Mar. 31, 2013 Cleco Corporation [Member] Guarantee Issued to Entergy Louisiana on behalf of Acadia [Member]	Mar. 31, 2013 Cleco Power [Member] Lignite Mining Agreement Guarantee [Member]	Feb. 28, 2010 Cleco Power [Member] Acadia Unit 1 Transaction [Member]	Mar. 31, 2013 APH [Member] Acadia Unit 2 Transaction [Member]	Mar. 31, 2013 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Mar. 31, 2012 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Feb. 23, 2010 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Mar. 31, 2013 Acadia Power Partners [Member] Acadia Unit 2 Transaction [Member]	Dec. 31, 2012 Acadia Power Partners [Member] Acadia Unit 2 Transaction [Member]	Apr. 29, 2011 Acadia Power Partners [Member] Acadia Unit 2 Transaction [Member]	Apr. 29, 2011 Acadia Power Partners [Member] APH [Member] Acadia Unit 2 and Facilities [Member]	Apr. 29, 2011 Cajun [Member] APH [Member] Acadia Unit 2 and Facilities [Member]	Mar. 31, 2013 Maximum [Member] Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]
Disclosures about Guarantees [Abstract]
Liability recognized on the balance sheets	$ 12,156,000			$ 200,000		$ 3,800,000
Maximum residual value of indemnification obligation												200,000					100,000
Indemnification liability representing risk of payment	7,850,000	8,150,000										7,800,000		21,800,000
Income from contractual expiration of indemnification								0	300,000	7,200,000		0	0
Guarantees, Fair Value Disclosure											13,500,000
Guarantor Obligations, Maximum Exposure, Undiscounted	4,225,000		10,000,000		298,800,000	72,500,000	30,000,000
Off-balance sheet commitments, expected termination dates [Abstract]
Net amount committed	4,225,000			42,400,000
Less than 1 year	3,725,000
1-3 years	0
3-5 years	0
More than 5 years	500,000
On-balance sheet guarantees, expected termination dates [Abstract]
Net amount committed	12,156,000			200,000		3,800,000
Less than 1 year	7,250,000
1-3 years	900,000
3-5 years	0
More than 5 years	4,006,000
Total off-balance sheet commitments and on-balance sheet guarantees, expected termination dates [Abstract]
Total net amount committed	16,381,000
Total less than 1 year	10,975,000
Total 1-3 years	900,000
Total 3-5 years	0
Total more than 5 years	$ 4,506,000
Ownership interest received (in hundredths)															100.00%
Ownership interest exchanged (in hundredths)																50.00%