Fair Value Accounting, Derivatives and Hedging (Details) (USD $)	3 Months Ended	9 Months Ended	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended	0 Months Ended	1 Months Ended		3 Months Ended	9 Months Ended					9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2013 Derivatives Not Designated As Hedging Instruments [Member]	Sep. 30, 2013 Derivatives Not Designated As Hedging Instruments [Member]	Sep. 30, 2013 Interest Rate Contract [Member] Derivatives Designated as Hedging Instruments [Member]	Sep. 30, 2012 Interest Rate Contract [Member] Derivatives Designated as Hedging Instruments [Member]	Sep. 30, 2013 Interest Rate Contract [Member] Derivatives Designated as Hedging Instruments [Member]	Sep. 30, 2012 Interest Rate Contract [Member] Derivatives Designated as Hedging Instruments [Member]	Dec. 31, 2012 Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member]	Sep. 30, 2013 Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member] AccumulatedDeferredFuel [Member]	Dec. 31, 2012 Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member] AccumulatedDeferredFuel [Member]	Nov. 14, 2011 Cleco Power [Member] Swap [Member]	May 30, 2013 Cleco Power [Member] Swap [Member]	May 07, 2013 Cleco Power [Member] Swap [Member]	Sep. 30, 2013 Cleco Power [Member] Derivatives Not Designated As Hedging Instruments [Member]	Sep. 30, 2013 Cleco Power [Member] Derivatives Not Designated As Hedging Instruments [Member]	Sep. 30, 2013 Cleco Power [Member] Interest Rate Contract [Member] Derivatives Designated as Hedging Instruments [Member]	Sep. 30, 2013 Cleco Power [Member] Energy Related Derivative [Member] MMBTU	Dec. 31, 2012 Cleco Power [Member] Energy Related Derivative [Member] MMBTU	Dec. 31, 2012 Cleco Power [Member] Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member]	Sep. 30, 2013 Cleco Power [Member] Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member] AccumulatedDeferredFuel [Member]	Dec. 31, 2012 Cleco Power [Member] Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member] AccumulatedDeferredFuel [Member]	Sep. 30, 2012 Cleco Power [Member] Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member] Fuel Used For Electric Generation [Member]	Sep. 30, 2012 Cleco Power [Member] Energy Related Derivative [Member] Derivatives Not Designated As Hedging Instruments [Member] Fuel Used For Electric Generation [Member]
Derivatives, Fair Value [Line Items]
Net gain (loss) on derivative recognized in income	$ 0	$ 0											$ 0	$ 0
Loss recognized in income																					600,000	8,200,000
Net unrealized gain (loss) on derivative								0											0
Net gain (loss) on derivatives not designated as hedging instruments									0											0
Balance of derivatives not designated as hedging instruments recorded on the balance sheet							0											0
Number of open derivative positions																0	0
Notional amount of derivative										50,000,000
Remaining maturity of derivative										30 years
Interest rate on derivative										3.05%
Gain (Loss) on the settlement of forward starting interest rate derivative												(3,300,000)
Gain (Loss) deferred as a regulatory asset on settlement of forward starting interest rate derivative												(2,900,000)
Gain (loss) on forward starting interest rate swap remaining in accumulated other comprehensive income (loss)												(400,000)
Amortization period of gain (loss) on settlement of the forward starting interest rate derivative											25 years
Schedule of Derivative Instruments [Abstract]
Gain (Loss) recognized in other comprehensive income (loss), effective portion			0	802,000	1,762,000	(733,000)
Gain (Loss) reclassified from accumulated OCI into income, effective portion			(86,000)	17,000	(165,000)	(39,000)
Net hedge ineffectiveness gain (loss)			0	0	3,300,000	2,600,000
Interest rate cash flow hedge gain (loss) to be reclassified during the next 12 months															$ (300,000)