Fair Value Accounting, Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Estimated Fair Value [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	$ 39,489	$ 118,951
Municipal bonds	10,203	0
Total Assets	49,692	118,951
Liability Description
Long-term debt, excluding debt issuance costs	1,579,674	1,542,867
Total Liabilities	1,582,301	1,551,533
Estimated Fair Value [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	5,336
Estimated Fair Value [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	2,627	3,330
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	0	0
Municipal bonds	0	0
Total Assets	0	0
Liability Description
Long-term debt, excluding debt issuance costs
Total Liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	0	0
Significant Other Observable Inputs (Level 2) [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	39,489	118,951
Municipal bonds	10,203	0
Total Assets	49,692	118,951
Liability Description
Long-term debt, excluding debt issuance costs	1,579,674	1,542,867
Total Liabilities	1,582,301	1,551,533
Significant Other Observable Inputs (Level 2) [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	5,336
Significant Other Observable Inputs (Level 2) [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	2,627	3,330
Significant Unobservable Inputs (Level 3) [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	0	0
Municipal bonds	0	0
Total Assets	0	0
Liability Description
Long-term debt, excluding debt issuance costs
Total Liabilities	0	0
Significant Unobservable Inputs (Level 3) [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	0
Significant Unobservable Inputs (Level 3) [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	0	0
Cleco Power [Member] \| Estimated Fair Value [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	33,292	99,955
Municipal bonds	10,203	0
Total Assets	43,495	99,955
Liability Description
Long-term debt, excluding debt issuance costs	1,554,674	1,532,867
Total Liabilities	1,557,301	1,541,533
Cleco Power [Member] \| Estimated Fair Value [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	5,336
Cleco Power [Member] \| Estimated Fair Value [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	2,627	3,330
Cleco Power [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	0	0
Municipal bonds	0	0
Total Assets	0	0
Liability Description
Long-term debt, excluding debt issuance costs
Total Liabilities	0	0
Cleco Power [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	0
Cleco Power [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	0	0
Cleco Power [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	33,292	99,955
Municipal bonds	10,203	0
Total Assets	43,495	99,955
Liability Description
Long-term debt, excluding debt issuance costs	1,554,674	1,532,867
Total Liabilities	1,557,301	1,541,533
Cleco Power [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	5,336
Cleco Power [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	2,627	3,330
Cleco Power [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Measured On A Recurring Basis [Member]
Asset Description
Institutional money market funds	0	0
Municipal bonds	0	0
Total Assets	0	0
Liability Description
Long-term debt, excluding debt issuance costs
Total Liabilities	0	0
Cleco Power [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Measured On A Recurring Basis [Member] \| Energy Market Derivatives [Member]
Liability Description
Derivative liabilities	0	0
Cleco Power [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Measured On A Recurring Basis [Member] \| Interest Rate Derivatives [Member]
Liability Description
Interest Rate Derivative Liabilities, at Fair Value	0	0
Cash and cash equivalents [Member]
Asset Description
Institutional money market funds	24,700
Cash and cash equivalents [Member] \| Cleco Power [Member]
Asset Description
Institutional money market funds	18,600
Restricted Cash and Cash Equivalents, Current [Member]
Asset Description
Institutional money market funds	8,800
Restricted Cash and Cash Equivalents, Current [Member] \| Cleco Power [Member]
Asset Description
Institutional money market funds	8,800
Restricted Cash and Cash Equivalents, Noncurrent [Member]
Asset Description
Institutional money market funds	5,400
Restricted Cash and Cash Equivalents, Noncurrent [Member] \| Cleco Power [Member]
Asset Description
Institutional money market funds	5,300
Restricted Investement, Noncurrent [Member]
Asset Description
Institutional money market funds	600
Municipal bonds	10,200
Restricted Investement, Noncurrent [Member] \| Cleco Power [Member]
Asset Description
Institutional money market funds	$ 600

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References+ Details

Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

+ References+ Details

- Definition

+ References+ Details