Regulatory Assets and Liabilities, Summary of Regulatory Assets and Liabilities (Details) (USD $)	9 Months Ended			9 Months Ended																	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 Cleco Power [Member]	Sep. 30, 2011 Cleco Power [Member]	Dec. 31, 2011 Cleco Power [Member]	Sep. 30, 2012 Cleco Power [Member] Total regulatory assets - other [Member]	Dec. 31, 2011 Cleco Power [Member] Total regulatory assets - other [Member]	Sep. 30, 2012 Cleco Power [Member] Mining costs [Member]	Dec. 31, 2011 Cleco Power [Member] Mining costs [Member]	Sep. 30, 2012 Cleco Power [Member] Interest costs [Member]	Dec. 31, 2011 Cleco Power [Member] Interest costs [Member]	Sep. 30, 2012 Cleco Power [Member] Asset removal costs [Member]	Dec. 31, 2011 Cleco Power [Member] Asset removal costs [Member]	Sep. 30, 2012 Cleco Power [Member] Postretirement plan costs [Member]	Dec. 31, 2011 Cleco Power [Member] Postretirement plan costs [Member]	Sep. 30, 2012 Cleco Power [Member] Tree trimming costs [Member]	Dec. 31, 2011 Cleco Power [Member] Tree trimming costs [Member]	Sep. 30, 2012 Cleco Power [Member] Training costs [Member]	Dec. 31, 2011 Cleco Power [Member] Training costs [Member]	Sep. 30, 2012 Cleco Power [Member] Storm surcredits, net [Member]	Dec. 31, 2011 Cleco Power [Member] Storm surcredits, net [Member]	Sep. 30, 2012 Cleco Power [Member] Construction carrying costs - asset [Member]	Dec. 31, 2011 Cleco Power [Member] Construction carrying costs - asset [Member]	Sep. 30, 2012 Cleco Power [Member] Lignite mining agreement contingency [Member]	Dec. 31, 2011 Cleco Power [Member] Lignite mining agreement contingency [Member]	Sep. 30, 2012 Cleco Power [Member] Power purchase agreement capacity costs [Member]	Dec. 31, 2011 Cleco Power [Member] Power purchase agreement capacity costs [Member]	Sep. 30, 2012 Cleco Power [Member] AFUDC equity gross-up [Member]	Dec. 31, 2011 Cleco Power [Member] AFUDC equity gross-up [Member]	Sep. 30, 2012 Cleco Power [Member] Rate case costs [Member]	Dec. 31, 2011 Cleco Power [Member] Rate case costs [Member]	Sep. 30, 2012 Cleco Power [Member] Acadia Unit 1 acquisition costs [Member]	Dec. 31, 2011 Cleco Power [Member] Acadia Unit 1 acquisition costs [Member]	Sep. 30, 2012 Cleco Power [Member] IRP/RFP costs [Member]	Dec. 31, 2011 Cleco Power [Member] IRP/RFP costs [Member]	Sep. 30, 2012 Cleco Power [Member] AMI pilot costs [Member]	Dec. 31, 2011 Cleco Power [Member] AMI pilot costs [Member]	Sep. 30, 2012 Cleco Power [Member] Financing costs [Member]	Dec. 31, 2011 Cleco Power [Member] Financing costs [Member]	Sep. 30, 2012 Cleco Power [Member] Biomass costs [Member]	Dec. 31, 2011 Cleco Power [Member] Biomass costs [Member]	Sep. 30, 2012 Cleco Power [Member] Construction carrying costs - liability [Member]	Dec. 31, 2011 Cleco Power [Member] Construction carrying costs - liability [Member]	Sep. 30, 2012 Cleco Power [Member] Fuel and purchased power [Member]	Dec. 31, 2011 Cleco Power [Member] Fuel and purchased power [Member]
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets				$ 6,000,000		$ 9,300,000	$ 271,154,000	$ 282,472,000	$ 17,206,000	$ 19,117,000	$ 6,394,000	$ 6,667,000	$ 851,000	$ 829,000	$ 126,349,000	$ 132,556,000	$ 6,335,000	$ 8,371,000	$ 7,369,000	$ 7,486,000	$ 5,958,000	$ 9,254,000	$ 6,262,000	$ 10,883,000	$ 3,781,000	$ 3,781,000	$ 5,921,000	$ 0	$ 73,906,000	$ 74,346,000	$ 716,000	$ 1,117,000	$ 2,892,000	$ 2,971,000	$ 156,000	$ 508,000	$ 54,000	$ 153,000	$ 6,851,000	$ 4,433,000	$ 153,000	$ 0			$ 1,715,000	$ 2,136,000
Regulatory liabilities																																											(8,251,000)	(40,322,000)
Total regulatory assets, net				484,051,000		458,707,000
Regulatory assets and liabilities - deferred taxes, net	219,433,000		214,421,000	219,433,000		214,421,000
Increase (Decrease) in Regulatory Assets and Liabilities	$ 30,532,000	$ 40,204,000		$ 30,532,000	$ 40,204,000																$ 3,300,000	$ 1,600,000