Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees (Details) (USD $)		6 Months Ended	12 Months Ended			6 Months Ended							3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011 Discrimination Complaint [Member]	Dec. 31, 2010 Discrimination Complaint [Member]	Jun. 30, 2011 City of Opelousas Litigation [Member]	Jun. 30, 2011 Other Litigation Matters [Member]	Jun. 30, 2011 Madison Unit 3 Commitments [Member]	Jun. 30, 2011 Cleco Corporation [Member] Guarantee Issued to Entergy Louisiana and Entergy Gulf States for Performance Obligations of Perryville [Member]	Jun. 30, 2011 Cleco Corporation [Member] Guarantee Issued to Entergy Mississippi on behalf of Attala [Member]	Jun. 30, 2011 Cleco Corporation [Member] Guarantee Issued to Cleco Power on behalf of Acadia [Member]	Jun. 30, 2011 Cleco Corporation [Member] Guarantee Issued to Entergy Louisiana on behalf of Acadia [Member]	Jun. 30, 2011 Cleco Power [Member] Obligations Under Standby Letter of Credit Issued to the Louisiana Department of Labor [Member]	Jun. 30, 2011 Cleco Power [Member] Lignite Mining Agreement Guarantee [Member]	Jun. 30, 2011 APH [Member] Acadia Unit 1 Transaction [Member]	Jun. 30, 2011 APH [Member] Acadia Unit 1 Transaction [Member]	Jun. 30, 2011 APH [Member] Acadia Unit 2 Transaction [Member]	Jun. 30, 2011 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Jun. 30, 2011 Acadia Power Partners [Member] Acadia Unit 1 Transaction [Member]	Jun. 30, 2011 Acadia Power Partners [Member] Acadia Unit 2 Transaction [Member]
Loss Contingencies [Line Items]
Number of current employees who filed complaint		8
Number of former employees who filed complaint		4
Minimum amount sought by plaintiffs		$ 35,000,000				$ 32,000,000
Minimum amount sought by additional plaintiff		2,500,000
Number of claims settled and dismissed		1
Number of pending claims		12		252
Number of training facilities where the EEOC has determined that there is reason to believe that violations had occurred		1
Settlement agreement with charging party and EEOC			0.1 million
Loss contingency, accrual						4,000,000
Threshold of claims exceeded as a result of demand for arbitration						1,000,000
Associated payment demanded upon excess of claims threshold						19,000,000
Range of possible loss, maximum					17,000,000	32,500,000
Range of possible loss, minimum					2,000,000	4,000,000
Fuel Expenses Included in Audit	3,200,000,000
Risks and uncertainties [Abstract]
Letter of credit required if senior unsecured credit rating is not maintained	20,000,000
Additional letter of credit required in the event of further downgrade	15,000,000
Guarantor Obligations [Line Items]
Face amount	4,225,000							500,000		10,000,000	3,725,000
Net amount	4,225,000						42,400,000	500,000		10,000,000	3,725,000
Percentage share of guarantee (in hundredths)											110.00%
Liability recognized on the balance sheets	34,249,000						200,000					3,800,000	6,800,000	6,800,000	10,900,000
Period (in years) over which average losses are determined											3
Fair value of indemnification liability recorded																13,500,000	13,500,000	21,800,000
Percentage of affiliate's indemnification liability accepted by entity (in hundredths)													50.00%	50.00%	50.00%
Indemnification received from third parties													6,800,000	6,800,000	10,900,000
Term of indemnification obligation														3y	3y		3y	3y
Maximum residual value of indemnification obligation																0	0	200,000
Indemnification liability representing risk of payment																8,400,000	8,400,000	21,800,000
Income from contractual expiration of indemnification													0	500,000		100,000	100,000
Estimated maximum projected payment									10,000,000	298,800,000		72,500,000				30,000,000	30,000,000
Off-balance sheet commitments, expected termination dates [Abstract]
NET AMOUNT COMMITTED	4,225,000						42,400,000	500,000		10,000,000	3,725,000
LESS THAN ONE YEAR	3,725,000
MORE THAN 5 YEARS	500,000
On-balance sheet guarantees, expected termination dates [Abstract]
NET AMOUNT COMMITTED	34,249,000						200,000					3,800,000	6,800,000	6,800,000	10,900,000
1-3 YEARS	30,243,000
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	38,474,000
Total LESS THAN ONE YEAR	3,725,000
Total 1-3 YEARS	30,243,000
Total MORE THAN 5 YEARS	$ 4,506,000