Miscellaneous Financial Information (Unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Quarterly Information [Line Items]
Operating revenue, net	$ 239,119,000	$ 351,581,000	$ 272,923,000	$ 253,690,000	$ 256,584,000	$ 343,892,000	$ 275,903,000	$ 272,287,000	$ 1,117,313,000	$ 1,148,666,000	$ 853,758,000
Operating income	49,326,000	116,180,000	70,295,000	65,234,000	59,359,000	99,987,000	80,094,000	55,901,000	301,035,000	295,341,000	106,809,000
Net income									195,848,000	255,391,000	106,307,000
Net income applicable to common stock	30,643,000	65,842,000	70,221,000	29,004,000	20,613,000	49,600,000	35,174,000	149,958,000	195,710,000	255,345,000	106,261,000
Basic net income per average share (in dollars per share)	$ 0.51	$ 1.09	$ 1.16	$ 0.48	$ 0.34	$ 0.82	$ 0.58	$ 2.49	$ 3.24	$ 4.23	$ 1.77
Diluted net income per average common share (in dollars per share)	$ 0.51	$ 1.08	$ 1.15	$ 0.48	$ 0.34	$ 0.82	$ 0.58	$ 2.48	$ 3.22	$ 4.20	$ 1.76
Dividends paid per common share (in dollars per share)	$ 0.3125	$ 0.28	$ 0.28	$ 0.25	$ 0.250	$ 0.250	$ 0.250	$ 0.225	$ 1.1225	$ 0.975	$ 0.900
Closing market price per share
High (in dollars per share)	$ 38.31	$ 36.14	$ 35.66	$ 34.51	$ 31.76	$ 30.00	$ 28.28	$ 27.67
Low (in dollars per share)	$ 32.36	$ 30.06	$ 33.68	$ 30.56	$ 29.59	$ 25.95	$ 24.91	$ 24.32
Cleco Power [Member]
Quarterly Information [Line Items]
Operating revenue, net	236,099,000	342,296,000	268,464,000	250,623,000	253,251,000	332,477,000	271,200,000	263,527,000	1,097,482,000	1,120,455,000	843,599,000
Operating income	53,638,000	110,175,000	75,548,000	67,819,000	62,484,000	94,989,000	81,308,000	53,869,000	307,180,000	292,650,000	111,462,000
Net income	23,278,000	53,833,000	35,694,000	30,030,000	23,821,000	52,335,000	39,089,000	32,160,000	142,835,000	147,405,000	111,166,000
Distribution to Cleco Corporation (as sole member)	$ 50,000,000	$ 25,000,000	$ 25,000,000	$ 30,000,000	$ 25,000,000	$ 50,000,000	$ 50,000,000	$ 25,000,000	$ 130,000,000	$ 150,000,000	$ 30,000,000