Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended		9 Months Ended
	Sep. 30, 2016	Apr. 12, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Cleco Power [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		$ 1,552,404				$ 1,552,404
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	$ 2,233		$ 271			2,720	$ 578
Balances	1,532,346			$ 1,532,346	$ 1,532,346	1,532,346
Cleco Power [Member] | Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	(16,605)	(17,092)	(16,981)			(17,092)	(17,288)
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	2,013					2,013
Amounts reclassified from accumulated other comprehensive income, net of tax	167		218			548	419
Net current-period other comprehensive income	2,233		271			2,720	578
Balances	(14,372)		(16,710)	(14,372)	(14,372)	(14,372)	(16,710)
Cleco Power [Member] | Total AOCI [Member] | Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax	53		53			159	159
Cleco Power [Member] | Postretirement Benefit Net Loss [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	(10,983)	(11,364)	(11,148)			(11,364)	(11,349)
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	2,013					2,013
Amounts reclassified from accumulated other comprehensive income, net of tax	167		218			548	419
Net current-period other comprehensive income	2,180		218			2,561	419
Balances	(8,803)		(10,930)	(8,803)	(8,803)	(8,803)	(10,930)
Cleco Power [Member] | Net Loss on Cash Flow Hedges [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	(5,622)	(5,728)	(5,833)			(5,728)	(5,939)
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	53		53			159	159
Balances	(5,569)		(5,780)	(5,569)	(5,569)	(5,569)	(5,780)
Cleco Power [Member] | Net Loss on Cash Flow Hedges [Member] | Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax	53		53			159	159
Predecessor [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		1,674,841			1,646,061	1,674,841
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income		647	639				2,010
Balances		1,646,061
Predecessor [Member] | Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		(26,585)	(31,294)		(25,938)	(26,585)	(32,665)
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		587	586				1,851
Net current-period other comprehensive income		647	639				2,010
Balances		(25,938)	(30,655)				(30,655)
Predecessor [Member] | Total AOCI [Member] | Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		60	53				159
Predecessor [Member] | Postretirement Benefit Net Loss [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		(20,857)	(25,461)		(20,270)	(20,857)	(26,726)
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		587	586				1,851
Net current-period other comprehensive income		587	586				1,851
Balances		(20,270)	(24,875)				(24,875)
Predecessor [Member] | Net Loss on Cash Flow Hedges [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		(5,728)	(5,833)		(5,668)	(5,728)	(5,939)
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income		60	53				159
Balances		(5,668)	(5,780)				(5,780)
Predecessor [Member] | Net Loss on Cash Flow Hedges [Member] | Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		$ 60	$ 53				$ 159
Successor [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances				2,158,141
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	(2,305)			(2,305)	(2,305)
Balances	2,057,542			2,057,542	2,057,542	2,057,542
Successor [Member] | Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	0			0
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	(2,308)				(2,308)
Amounts reclassified from accumulated other comprehensive income, net of tax	3				3
Net current-period other comprehensive income	(2,305)			(2,305)	(2,305)
Balances	(2,305)			(2,305)	(2,305)	(2,305)
Successor [Member] | Postretirement Benefit Net Loss [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	0			0
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	(2,308)				(2,308)
Amounts reclassified from accumulated other comprehensive income, net of tax	3				3
Net current-period other comprehensive income	(2,305)				(2,305)
Balances	(2,305)			(2,305)	(2,305)	(2,305)
Successor [Member] | Net Loss on Cash Flow Hedges [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	0			0
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	0				0
Balances	$ 0			$ 0	$ 0	$ 0