Fair Value Accounting, Concentration of Risk (Details) (Maximum Amount of Loss [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2013
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Concentrations of credit risk through short-term investments	$ 48.5
Concentrations of credit risk through short-term investments in cash equivalents	39.6
Concentrations of credit risk through short-term investments in restricted cash equivalents	8.9
Cleco Power [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Concentrations of credit risk through short-term investments	46.4
Concentrations of credit risk through short-term investments in cash equivalents	37.6
Concentrations of credit risk through short-term investments in restricted cash equivalents	$ 8.8

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph a, f, g

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558

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+ Details