Debt, Total Indebtedness (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 1,268,715,000	$ 1,265,529,000
Long-term Line of Credit	0
Barge Lease Obligations	1,819,000	4,425,000
Gross amount of long-term debt	1,270,534,000	1,269,954,000
Less: Long-term Debt due within one year	17,896,000	16,814,000
Less: lease obligations classified as long-term debt due within one year	1,819,000	2,607,000
Unamortized Debt Discount	(6,342,000)	(6,885,000)
Unamortized Debt Issuance Costs	(9,421,000)	(9,609,000)
Long-term debt, net	1,235,056,000	1,234,039,000
Cleco Power's senior notes, 6.65%, due 2018 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	0	250,000,000
Cleco Power's senior notes, 3.68%, due 2025 [Member] [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	75,000,000	75,000,000
Cleco Power's senior notes, 3.47%, due 2026 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	130,000,000	0
Cleco Powers Senior Notes 4.33% due 2027 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	50,000,000	50,000,000
Cleco Power's senior notes, 3.57%, due 2028 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	200,000,000	0
Cleco Power's senior notes, 6.50%, due 2035 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	295,000,000	295,000,000
Cleco Power's senior notes, 6.00%, due 2040 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	250,000,000	250,000,000
Cleco Power's senior notes 5.12% due 2041 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	100,000,000	100,000,000
Series A GO Zone bonds, 2.00%, due 2038, mandatory tender in 2020 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	50,000,000	50,000,000
Series B GO Zone bonds, 4.25%, due 2036 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	50,000,000	50,000,000
Cleco Power's solid waste disposal facility bonds, 4.70%, due 2036, callable after November 1, 2016 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	0	60,000,000
Cleco Katrina/Rita's storm recovery bonds, 4.41%, due 2020 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	1,115,000	17,929,000
Cleco Katrina/Rita's storm recovery bonds, 5.61%, due 2023 [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Unsecured Debt	67,600,000	67,600,000
Cleco Katrina Rita Storm Recovery Bonds [Member] \| Cleco Power [Member]
Debt Instrument [Line Items]
Less: Long-term Debt due within one year	17,900,000
Successor [Member]
Debt Instrument [Line Items]
Less: lease obligations classified as long-term debt due within one year	1,800,000
Unamortized Debt Issuance Costs	(11,700,000)
Long-term debt, net	2,738,571,000
Successor [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	0
Unamortized Debt Issuance Costs	(2,261,000)
Long Term Debt. Reconciliation, Fair Value Adjustment	155,776,000
Successor [Member] \| Cleco Holdings' senior notes, 3.250%, due 2023 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Unsecured Debt	165,000,000
Successor [Member] \| Cleco Katrina Rita Storm Recovery Bonds [Member]
Debt Instrument [Line Items]
Less: Long-term Debt due within one year	17,900,000
Successor [Member] \| Cleco Holdings' senior notes, 3.743%, due 2026 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Unsecured Debt	535,000,000
Successor [Member] \| Cleco Holdings' senior notes, 4.973%, due 2046 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Unsecured Debt	350,000,000
Successor [Member] \| Cleco Corporate Holdings debt, variable rate, due 2021 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Bank Term Loan	$ 300,000,000
Predecessor [Member]
Debt Instrument [Line Items]
Unamortized Debt Issuance Costs		(9,900,000)
Long-term debt, net		1,267,703,000
Predecessor [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Long-term Line of Credit		34,000,000
Unamortized Debt Issuance Costs		(336,000)
Long Term Debt. Reconciliation, Fair Value Adjustment		0
Predecessor [Member] \| Cleco Holdings' senior notes, 3.250%, due 2023 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Unsecured Debt		0
Predecessor [Member] \| Cleco Holdings' senior notes, 3.743%, due 2026 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Unsecured Debt		0
Predecessor [Member] \| Cleco Holdings' senior notes, 4.973%, due 2046 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Unsecured Debt		0
Predecessor [Member] \| Cleco Corporate Holdings debt, variable rate, due 2021 [Member] \| Cleco Holdings [Member]
Debt Instrument [Line Items]
Bank Term Loan		$ 0

Long Term Debt. Reconciliation, Fair Value Adjustment

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of the fee that accompanies borrowing money under the debt instrument.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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