Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Apr. 12, 2016	Jun. 30, 2016	Jun. 30, 2015
Predecessor [Member]
Operating activities [Abstract]
Net (loss) income		$ (3,960)		$ 57,156
Adjustments to reconcile net income to net cash provided by operating activities [Abstract]
Depreciation and amortization		45,869		76,951
Gain on sale of asset		(1,095)		0
Unearned compensation expense		3,276		3,341
Allowance for equity funds used during construction		(724)		(1,537)
Net deferred income taxes		2,219		33,367
Deferred fuel costs		977		7,251
Cash surrender value of company-/trust-owned life insurance		(840)		(366)
Provision for merger commitments		0		0
Changes in assets and liabilities [Abstract]
Accounts receivable		(1,865)		(8,062)
Accounts and notes receivable, affiliate		0		0
Unbilled revenue		563		(4,866)
Fuel inventory and materials and supplies		19,312		4,973
Prepayments		2,395		1,295
Accounts payable		8,348		(27,652)
Accounts and notes payable, affiliate		0		0
Customer deposits		3,342		6,104
Postretirement benefit obligations		9,746		6,878
Regulatory assets and liabilities, net		5,178		8,764
Other deferred accounts		6,878		(7,872)
Taxes accrued		10,820		16,959
Interest accrued		17,909		1,112
Deferred compensation		(793)		(908)
Other operating		2,224		1,579
Net cash provided by operating activities		129,779		174,467
Investing activities [Abstract]
Additions to property, plant, and equipment		(42,392)		(78,180)
Allowance for equity funds used during construction		724		1,537
Proceeds from sale of property		1,932		0
Premiums paid on trust-owned life insurance		0		(1,375)
Contributions to equity investment in investee		(2,450)		(840)
Return of equity investment in tax credit fund		476		1,172
Contributions to tax credit fund		0		(923)
Transfer of cash (to) from restricted accounts, net		4,847		(41)
Other investing		53		459
Net cash used in investing activities		(36,810)		(78,191)
Financing activities [Abstract]
Draws on credit facilities		3,000		62,000
Payments on credit facilities		(10,000)		(87,000)
Issuance of long-term debt		0		0
Repayment of long-term debt		(8,546)		(43,053)
Payment of financing costs		(43)		(154)
Dividends paid		(24,579)		(48,869)
Contribution from member		0		0
Distributions to parent		0		0
Other financing		(717)		(1,194)
Net cash provided by (used in) financing activities		(40,885)		(118,270)
Net (decrease) increase in cash and cash equivalents		52,084		(21,994)
Cash and cash equivalents at beginning of period	$ 120,330	68,246	$ 68,246	44,423
Cash and cash equivalents at end of period		120,330		22,429
Supplementary cash flow information [Abstract]
Interest paid, net of amount capitalized		2,478		36,751
Income taxes paid (refunded), net		(481)		306
Supplementary non-cash investing and financing activities [Abstract]
Accrued additions to property, plant, and equipment		10,619		7,674
Additions to property, plant, and equipment - ARO		961		0
Successor [Member]
Operating activities [Abstract]
Net (loss) income	(81,914)
Adjustments to reconcile net income to net cash provided by operating activities [Abstract]
Depreciation and amortization	57,718
Gain on sale of asset	0
Unearned compensation expense	361
Allowance for equity funds used during construction	(748)
Net deferred income taxes	(47,264)
Deferred fuel costs	(7,717)
Cash surrender value of company-/trust-owned life insurance	(1,761)
Provision for merger commitments	150,840
Changes in assets and liabilities [Abstract]
Accounts receivable	(5,360)
Accounts and notes receivable, affiliate	(3,786)
Unbilled revenue	(12,988)
Fuel inventory and materials and supplies	12,765
Prepayments	(2,425)
Accounts payable	(19,143)
Accounts and notes payable, affiliate	146
Customer deposits	2,787
Postretirement benefit obligations	936
Regulatory assets and liabilities, net	4,104
Other deferred accounts	(7,109)
Taxes accrued	(8,161)
Interest accrued	(11,760)
Deferred compensation	(1,436)
Other operating	2,705
Net cash provided by operating activities	20,790
Investing activities [Abstract]
Additions to property, plant, and equipment	(43,623)
Allowance for equity funds used during construction	748
Proceeds from sale of property	159
Premiums paid on trust-owned life insurance	0
Contributions to equity investment in investee	0
Return of equity investment in tax credit fund	475
Contributions to tax credit fund	0
Transfer of cash (to) from restricted accounts, net	(147,830)
Other investing	104
Net cash used in investing activities	(189,967)
Financing activities [Abstract]
Draws on credit facilities	15,000
Payments on credit facilities	(15,000)
Issuance of long-term debt	1,350,000
Repayment of long-term debt	(1,350,000)
Payment of financing costs	(5,830)
Dividends paid	(572)
Contribution from member	100,720
Distributions to parent	(28,000)
Other financing	(559)
Net cash provided by (used in) financing activities	65,759
Net (decrease) increase in cash and cash equivalents	(103,418)
Cash and cash equivalents at beginning of period	120,330
Cash and cash equivalents at end of period	16,912	120,330	16,912
Supplementary cash flow information [Abstract]
Interest paid, net of amount capitalized	37,466
Income taxes paid (refunded), net	256
Supplementary non-cash investing and financing activities [Abstract]
Accrued additions to property, plant, and equipment	19,668
Additions to property, plant, and equipment - ARO	0
Cleco Power [Member]
Operating activities [Abstract]
Net (loss) income			(40,350)	60,418
Adjustments to reconcile net income to net cash provided by operating activities [Abstract]
Depreciation and amortization			79,059	75,591
Gain on sale of asset			(1,095)	0
Allowance for equity funds used during construction			(1,472)	(1,537)
Net deferred income taxes			(22,438)	34,583
Deferred fuel costs			(6,740)	7,251
Provision for merger commitments			150,840	0
Changes in assets and liabilities [Abstract]
Accounts receivable			(6,914)	(8,204)
Accounts and notes receivable, affiliate			(680)	5,857
Unbilled revenue			(12,425)	(4,866)
Fuel inventory and materials and supplies			32,077	4,973
Prepayments			(512)	(867)
Accounts payable			(13,238)	(22,311)
Accounts and notes payable, affiliate			(4,129)	(2,619)
Customer deposits			6,129	6,104
Postretirement benefit obligations			2,426	3,533
Regulatory assets and liabilities, net			8,854	8,764
Other deferred accounts			(231)	(6,409)
Taxes accrued			(11,129)	18,949
Interest accrued			1,102	1,099
Other operating			5,056	1,888
Net cash provided by operating activities			164,190	182,197
Investing activities [Abstract]
Additions to property, plant, and equipment			(85,936)	(78,010)
Allowance for equity funds used during construction			1,472	1,537
Proceeds from sale of property			2,091	0
Contributions to equity investment in investee			(2,450)	(840)
Transfer of cash (to) from restricted accounts, net			(142,983)	(41)
Other investing			157	459
Net cash used in investing activities			(227,649)	(76,895)
Financing activities [Abstract]
Draws on credit facilities			15,000	20,000
Payments on credit facilities			(15,000)	(40,000)
Repayment of long-term debt			(8,546)	(43,053)
Contribution from member			50,000	0
Distributions to parent			(35,000)	(60,000)
Other financing			(1,390)	(1,348)
Net cash provided by (used in) financing activities			5,064	(124,401)
Net (decrease) increase in cash and cash equivalents			(58,395)	(19,099)
Cash and cash equivalents at beginning of period		$ 65,705	65,705	39,162
Cash and cash equivalents at end of period	$ 7,310		7,310	20,063
Supplementary cash flow information [Abstract]
Interest paid, net of amount capitalized			35,746	36,394
Income taxes paid (refunded), net			(485)	565
Supplementary non-cash investing and financing activities [Abstract]
Accrued additions to property, plant, and equipment			19,571	7,639
Additions to property, plant, and equipment - ARO			$ 961	$ 0