Disclosures about Segments (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Segment Reporting Information [Line Items]
Electric operations	$ 324,532	$ 325,629	$ 823,484	$ 839,528
Tolling operations	9,133	11,153	16,137	23,016
Other operations	16,064	13,305	41,775	34,425
Electric customer credits	1,852	(6,314)	(3,405)	(6,314)
Affiliate revenue	0	119	202	1,426
Operating revenue	351,581	343,892	878,193	892,081
Depreciation	30,557	28,847	89,641	82,899
Interest charges	25,779	25,068	78,011	72,020
Interest income	509	128	794	369
Equity income (loss) from investees, before tax	(1)	2,494	62,051	39,212
Gain on toll settlement			0	148,402
Federal and state income tax expense (benefit)	24,737	30,155	73,451	127,411
Segment profit (loss)	65,842	49,612	165,205	234,768
Additions to long-lived assets	80,368	36,203	158,033	400,058
Equity investment in investees	13,081		13,081		86,732
Total segment assets	4,071,541		4,071,541		4,161,410
Reconciliation of segment profit to consolidated profit:
Segment profit (loss)	65,842	49,612	165,205	234,768
Unallocated items:
Preferred dividends requirements, net of tax	0	12	26	35
Preferred stock redemption costs, net of tax			112	0
Net income applicable to common stock	65,842	49,600	165,067	234,733
Cleco Power [Member]
Segment Reporting Information [Line Items]
Electric operations	324,532	325,629	823,484	839,528
Other operations	15,565	12,819	40,261	32,959
Electric customer credits	1,852	(6,314)	(3,405)	(6,314)
Affiliate revenue	347	343	1,041	1,029
Operating revenue	342,296	332,477	861,381	867,202
Depreciation	28,859	27,133	84,543	77,941
Interest charges	25,306	16,044	74,029	57,104
Interest income	276	117	557	351
Federal and state income tax expense (benefit)	31,656	26,568	61,935	58,299
Segment profit (loss)	53,833	52,335	119,557	123,584
Additions to long-lived assets	76,213	35,308	152,082	397,301
Equity investment in investees	13,073		13,073		13,073
Total segment assets	3,774,385		3,774,385		3,795,205
Reconciliation of segment profit to consolidated profit:
Segment profit (loss)	53,833	52,335	119,557	123,584
Midstream [Member]
Segment Reporting Information [Line Items]
Tolling operations	9,133	11,153	16,137	23,016
Other operations	1	1	8	2
Affiliate revenue		5	45	924
Operating revenue	9,134	11,159	16,190	23,942
Depreciation	1,457	1,446	4,370	4,334
Interest charges	752	1,109	1,963	5,972
Interest income	5		6
Equity income (loss) from investees, before tax		2,494	62,053	39,211
Gain on toll settlement				148,402
Federal and state income tax expense (benefit)	444	2,758	21,296	72,905
Segment profit (loss)	5,946	5,156	39,274	117,176
Additions to long-lived assets	4,074	454	5,202	1,576
Equity investment in investees					73,648
Total segment assets	234,537		234,537		316,165
Reconciliation of segment profit to consolidated profit:
Segment profit (loss)	5,946	5,156	39,274	117,176
Reconciling Items [Member]
Segment Reporting Information [Line Items]
Other operations	500	488	1,511	1,470
Affiliate revenue	13,448	11,290	37,544	34,783
Operating revenue	13,948	11,778	39,055	36,253
Depreciation	241	268	728	624
Interest charges	(308)	7,949	1,891	9,575
Interest income	199	44	103	649
Equity income (loss) from investees, before tax	(1)		(2)	1
Federal and state income tax expense (benefit)	(7,363)	830	(9,781)	(3,793)
Segment profit (loss)	6,063	(7,879)	6,374	(5,992)
Additions to long-lived assets	81	441	749	1,181
Equity investment in investees	9		9		11
Total segment assets	200,854		200,854		401,663
Reconciliation of segment profit to consolidated profit:
Segment profit (loss)	6,063	(7,879)	6,374	(5,992)
Eliminations [Member]
Segment Reporting Information [Line Items]
Other operations	(2)	(3)	(5)	(6)
Affiliate revenue	(13,795)	(11,519)	(38,428)	(35,310)
Operating revenue	(13,797)	(11,522)	(38,433)	(35,316)
Interest charges	29	(34)	128	(631)
Interest income	29	(33)	128	(631)
Federal and state income tax expense (benefit)		(1)	1
Equity investment in investees	(1)		(1)
Total segment assets	$ (138,235)		$ (138,235)		$ (351,623)