Summary of Significant Accounting Policies, Reclassifications (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Reclassifications [Abstract]
Accounts receivable	$ 6,253	$ (13,958)
Accounts payable	(53,174)	(35,617)
Net cash provided by operating activities	41,373	2,302
Additions to property, plant, and equipment	(39,380)	(21,883)
Net cash used in investing activities	(40,825)	(19,537)
Net decrease in cash and cash equivalents	(46,327)	(53,937)
Cash and cash equivalents at beginning of period	93,576	191,128
Cash and cash equivalents at end of period	47,249	137,191
Accrued additions to property, plant, and equipment	6,974	23,245
Cash Flows Related To Accruals for Property, Plant and Equipment [Member]
Reclassifications [Abstract]
Accounts receivable	(13,958)
Accounts payable	(35,617)
Retainage payable	(13)
Net cash provided by operating activities	2,302
Additions to property, plant, and equipment	(21,883)
Net cash used in investing activities	(19,537)
Net decrease in cash and cash equivalents	(53,937)
Cash and cash equivalents at beginning of period	191,128
Cash and cash equivalents at end of period	137,191
Accrued additions to property, plant, and equipment	23,245
Cash Flows Related To Accruals for Property, Plant and Equipment [Member] | As Reported [Member]
Reclassifications [Abstract]
Accounts receivable	5,042
Accounts payable	(31,823)
Retainage payable	1,004
Net cash provided by operating activities	26,111
Additions to property, plant, and equipment	(45,692)
Net cash used in investing activities	(43,346)
Net decrease in cash and cash equivalents	(53,937)
Cash and cash equivalents at beginning of period	191,128
Cash and cash equivalents at end of period	137,191
Accrued additions to property, plant, and equipment	17,155
Cleco Power [Member]
Reclassifications [Abstract]
Accounts receivable	5,767	(10,720)
Accounts payable	(43,623)	(34,966)
Net cash provided by operating activities	47,513	5,299
Additions to property, plant, and equipment	(38,507)	(20,720)
Net cash used in investing activities	(30,759)	(8,955)
Net decrease in cash and cash equivalents	(31,573)	(60,472)
Cash and cash equivalents at beginning of period	67,458	184,912
Cash and cash equivalents at end of period	35,885	124,440
Accrued additions to property, plant, and equipment	11,262	23,246
Cleco Power [Member] | Cash Flows Related To Accruals for Property, Plant and Equipment [Member]
Reclassifications [Abstract]
Accounts receivable	(10,720)
Accounts payable	(34,966)
Retainage payable	(13)
Net cash provided by operating activities	5,299
Additions to property, plant, and equipment	(20,720)
Net cash used in investing activities	(8,955)
Net decrease in cash and cash equivalents	(60,472)
Cash and cash equivalents at beginning of period	184,912
Cash and cash equivalents at end of period	124,440
Accrued additions to property, plant, and equipment	23,246
Cleco Power [Member] | Cash Flows Related To Accruals for Property, Plant and Equipment [Member] | As Reported [Member]
Reclassifications [Abstract]
Accounts receivable	8,280
Accounts payable	(31,202)
Retainage payable	1,004
Net cash provided by operating activities	29,081
Additions to property, plant, and equipment	(44,501)
Net cash used in investing activities	(32,737)
Net decrease in cash and cash equivalents	(60,472)
Cash and cash equivalents at beginning of period	184,912
Cash and cash equivalents at end of period	124,440
Accrued additions to property, plant, and equipment	$ 17,233