Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets [Abstract]
Cash and cash equivalents	$ 17,329	$ 44,423
Restricted cash and cash equivalents	3,702	8,986
Customer accounts receivable (less allowance for doubtful accounts)	61,503	41,500
Other accounts receivable	21,264	28,098
Unbilled revenue	40,494	38,475
Fuel inventory, at average cost	62,251	64,747
Material and supplies inventory, at average cost	77,041	71,124
Energy risk management assets	14,563	10,776
Accumulated deferred federal and state income taxes, net	26,083	76,785
Accumulated deferred fuel	18,662	21,554
Cash surrender value of company-/trust-owned life insurance policies	71,480	71,167
Prepayments	7,161	10,284
Regulatory assets	14,497	12,212
Other current assets	3,237	473
Total current assets	439,267	500,604
Property, plant, and equipment [Abstract]
Property, plant, and equipment	4,616,808	4,508,960
Accumulated depreciation	(1,512,711)	(1,442,960)
Net property, plant, and equipment	3,104,097	3,066,000
Construction work in progress	76,971	99,458
Total property, plant, and equipment, net	3,181,068	3,165,458
Equity investment in investees	16,380	14,540
Prepayments	4,355	4,891
Restricted cash and cash equivalents	15,878	15,130
Regulatory assets - deferred taxes, net	236,341	234,370
Regulatory assets	287,031	311,867
Net investment in direct financing lease	13,473	13,498
Intangible asset	78,608	90,642
Tax credit fund investment, net	8,488	7,251
Other deferred charges	24,460	20,822
Total assets	4,305,349	4,379,073
Current liabilities [Abstract]
Long-term debt due within one year	19,382	18,272
Accounts payable	85,198	127,268
Customer deposits	54,910	53,411
Provision for rate refund	4,164	2,264
Taxes payable	28,282	2,197
Interest accrued	21,909	8,669
Energy risk management liabilities	488	827
Regulatory liabilities - other	468	312
Deferred compensation	9,975	11,374
Other current liabilities	16,014	13,176
Total current liabilities	240,790	237,770
Long-term liabilities and deferred credits [Abstract]
Accumulated deferred federal and state income taxes, net	936,170	918,858
Accumulated deferred investment tax credits	3,474	4,161
Postretirement benefit obligations	205,084	197,623
Regulatory liabilities - other	0	312
Restricted storm reserve	15,859	14,916
Other deferred credits	25,005	28,510
Total long-term liabilities and deferred credits	1,185,592	1,164,380
Long-term debt, net	1,207,217	1,349,653
Total liabilities	$ 2,633,599	$ 2,751,803
Commitments and Contingencies (Note 11)
Shareholders’ equity [Abstract]
Common stock	$ 61,059	$ 61,051
Premium on common stock	417,022	415,482
Retained earnings	1,247,506	1,208,712
Treasury stock, at cost	(23,182)	(25,310)
Accumulated other comprehensive loss	(30,655)	(32,665)
Total common shareholders’ equity	1,671,750	1,627,270
Total liabilities and shareholders’ equity	4,305,349	4,379,073
Cleco Power [Member]
Current assets [Abstract]
Cash and cash equivalents	15,821	39,162
Restricted cash and cash equivalents	3,702	8,986
Customer accounts receivable (less allowance for doubtful accounts)	61,503	41,500
Accounts receivable - affiliate	1,030	23,621
Other accounts receivable	21,075	27,949
Unbilled revenue	40,494	38,475
Fuel inventory, at average cost	62,251	64,747
Material and supplies inventory, at average cost	77,041	71,124
Energy risk management assets	14,563	10,776
Accumulated deferred federal and state income taxes, net	0	6,725
Accumulated deferred fuel	18,662	21,554
Cash surrender value of company-/trust-owned life insurance policies	19,923	19,678
Prepayments	6,078	7,283
Regulatory assets	14,497	12,212
Other current assets	2,471	368
Total current assets	359,111	394,160
Property, plant, and equipment [Abstract]
Property, plant, and equipment	4,601,293	4,495,490
Accumulated depreciation	(1,502,208)	(1,433,206)
Net property, plant, and equipment	3,099,085	3,062,284
Construction work in progress	76,675	96,702
Total property, plant, and equipment, net	3,175,760	3,158,986
Equity investment in investees	16,372	14,532
Prepayments	4,355	4,891
Restricted cash and cash equivalents	15,857	15,109
Regulatory assets - deferred taxes, net	236,341	234,370
Regulatory assets	287,031	311,867
Intangible asset	78,608	90,642
Other deferred charges	22,490	18,429
Total assets	4,195,925	4,242,986
Current liabilities [Abstract]
Long-term debt due within one year	19,382	18,272
Accounts payable	78,097	116,925
Accounts payable - affiliate	7,622	7,760
Customer deposits	54,910	53,411
Provision for rate refund	4,164	2,264
Taxes payable	39,673	3,115
Interest accrued	21,906	9,224
Energy risk management liabilities	488	827
Accumulated deferred federal and state income taxes, net	3,678	0
Regulatory liabilities - other	468	312
Other current liabilities	12,254	9,380
Total current liabilities	242,642	221,490
Long-term liabilities and deferred credits [Abstract]
Accumulated deferred federal and state income taxes, net	1,029,251	1,001,332
Accumulated deferred investment tax credits	3,474	4,161
Postretirement benefit obligations	145,936	135,825
Regulatory liabilities - other	0	312
Restricted storm reserve	15,859	14,916
Other deferred credits	24,030	26,439
Total long-term liabilities and deferred credits	1,218,550	1,182,985
Long-term debt, net	1,169,217	1,292,653
Total capitalization	$ 2,734,733	$ 2,838,511
Commitments and Contingencies (Note 11)
Shareholders’ equity [Abstract]
Total common shareholders’ equity	$ 1,565,516	$ 1,545,858
Total liabilities and shareholders’ equity	$ 4,195,925	$ 4,242,986