Pension Plan and Employee Benefits, Pension Plan and Other Benefits Plan (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended	3 Months Ended		9 Months Ended			1 Months Ended	3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2013 Pension Benefits [Member]	Sep. 30, 2012 Pension Benefits [Member]	Sep. 30, 2013 Pension Benefits [Member]	Sep. 30, 2012 Pension Benefits [Member]	Dec. 31, 2012 Pension Benefits [Member]	Sep. 30, 2013 Other Benefits [Member]	Sep. 30, 2012 Other Benefits [Member]	Sep. 30, 2013 Other Benefits [Member]	Sep. 30, 2012 Other Benefits [Member]	Dec. 31, 2012 Other Benefits [Member]	Jan. 31, 2013 Cleco Power [Member] Pension Benefits [Member]	Sep. 30, 2013 Cleco Power [Member] Other Benefits [Member]	Sep. 30, 2012 Cleco Power [Member] Other Benefits [Member]	Sep. 30, 2013 Cleco Power [Member] Other Benefits [Member]	Sep. 30, 2012 Cleco Power [Member] Other Benefits [Member]	Dec. 31, 2012 Cleco Power [Member] Other Benefits [Member]	Sep. 30, 2013 Other Subsidiaries [Member] Pension Benefits [Member]	Sep. 30, 2012 Other Subsidiaries [Member] Pension Benefits [Member]	Sep. 30, 2013 Other Subsidiaries [Member] Pension Benefits [Member]	Sep. 30, 2012 Other Subsidiaries [Member] Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension contributions designated for prior plan year											$ 34,000,000
Discretionary contributions to the pension plan					0
Current portion of other benefits liability						3,100,000		3,100,000		3,100,000		2,900,000		2,900,000		2,900,000
Components of periodic benefit costs
Service cost	2,472,000	2,078,000	7,417,000	6,234,000		614,000	303,000	1,242,000	1,096,000
Interest cost	4,485,000	4,563,000	13,455,000	13,690,000		214,000	334,000	1,176,000	1,287,000
Expected return on plan assets	(5,861,000)	(5,201,000)	(17,584,000)	(15,604,000)		0	0	0	0
Transition obligation	0	0	0	0		6,000	5,000	15,000	15,000
Prior period service cost (credit)	(18,000)	(18,000)	(53,000)	(53,000)		0	0	0	0
Net loss	3,304,000	2,087,000	9,913,000	6,259,000		213,000	112,000	849,000	512,000
Net periodic benefit cost	$ 4,382,000	$ 3,509,000	$ 13,148,000	$ 10,526,000		$ 1,047,000	$ 754,000	$ 3,282,000	$ 2,910,000			$ 900,000	$ 700,000	$ 2,800,000	$ 2,500,000		$ 600,000	$ 500,000	$ 1,900,000	$ 1,600,000