Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, Disclosures about Guarantees (Details) (USD $)								3 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Feb. 28, 2010 Guarantee Issued to Cleco Power on behalf of Acadia [Member]	Sep. 30, 2012 Cleco Corporation [Member] Guarantee Issued to Entergy Louisiana and Entergy Gulf States for Performance Obligations of Perryville [Member]	Sep. 30, 2012 Cleco Corporation [Member] Guarantee Issued to Entergy Louisiana on behalf of Acadia [Member]	Sep. 30, 2012 Cleco Power [Member] Lignite Mining Agreement Guarantee [Member]	Feb. 28, 2010 Cleco Power [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2011 APH [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2012 APH [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2011 APH [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2012 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2011 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2012 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2011 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Feb. 23, 2010 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Sep. 30, 2012 Acadia Power Partners [Member] Acadia Unit 2 Transaction [Member]	Sep. 30, 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]	Apr. 29, 2011 Cajun [Member] APH [Member]	Sep. 30, 2012 Maximum [Member] Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]
Disclosures about Guarantees [Abstract]
Liability recognized on the balance sheets	$ 14,356,000			$ 200,000		$ 3,800,000
Term of indemnification obligation											3 years					3 years
Maximum residual value of indemnification obligation																200,000	200,000				100,000
Indemnification liability representing risk of payment	10,350,000	29,357,000									400,000		400,000		13,500,000	10,000,000	10,000,000	21,800,000
Income from contractual expiration of indemnification								0	0	500,000	0	1,000,000	7,200,000	1,100,000		0	11,800,000
Estimated maximum projected payment			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 ONE 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	14,356,000			200,000		3,800,000
LESS THAN ONE YEAR	0
1-3 YEARS	10,350,000
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	18,581,000
Total LESS THAN ONE YEAR	3,725,000
Total 1-3 YEARS	10,350,000
Total 3-5 YEARS	0
Total MORE THAN 5 YEARS	$ 4,506,000
Equity Method Investment, Ownership Percentage																			100.00%
Ownership interest exchanged (in hundredths)																				50.00%