Fair Value Accounting, Fair Value Measurements and Disclosures(Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Asset Description
Institutional money market funds	$ 67,411,000us-gaap_InvestmentsFairValueDisclosure		$ 63,701,000us-gaap_InvestmentsFairValueDisclosure
FTR assets	2,245,000		10,776,000
Total Assets	69,656,000us-gaap_AssetsFairValueDisclosure		74,477,000us-gaap_AssetsFairValueDisclosure
Liability Description
Long-term debt	1,587,097,000us-gaap_LongTermDebtFairValue		1,601,816,000us-gaap_LongTermDebtFairValue
FTR liabilities	432,000		827,000
Total Liabilities	1,587,529,000us-gaap_LiabilitiesFairValueDisclosure		1,602,643,000us-gaap_LiabilitiesFairValueDisclosure
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Transfers between fair value levels	0		0
Cash and Cash Equivalents [Member]
Asset Description
Institutional money market funds	48,800,000
Restricted Cash and Cash Equivalents, Current [Member]
Asset Description
Institutional money market funds	3,200,000
Restricted Cash and Cash Equivalents, Noncurrent [Member]
Asset Description
Institutional money market funds	15,400,000
Cleco Power [Member]
Asset Description
Institutional money market funds	65,890,000		58,680,000
FTR assets	2,245,000		10,776,000
Total Assets	68,135,000		69,456,000
Liability Description
Long-term debt	1,525,097,000		1,544,816,000
FTR liabilities	432,000		827,000
Total Liabilities	1,525,529,000		1,545,643,000
Cleco Power [Member] \| Cash and Cash Equivalents [Member]
Asset Description
Institutional money market funds	47,300,000
Cleco Power [Member] \| Restricted Cash and Cash Equivalents, Current [Member]
Asset Description
Institutional money market funds	3,200,000
Cleco Power [Member] \| Restricted Cash and Cash Equivalents, Noncurrent [Member]
Asset Description
Institutional money market funds	15,400,000
FTRs [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning fair value of FTR assets (liabilities), net	9,949,000	8,638,000
Unrealized losses	(1,710,000)	(1,060,000)
Net purchases and settlements	(6,426,000)	(3,670,000)
Ending fair value of FTR assets (liabilities), net	1,813,000	3,908,000
FTRs [Member] \| Low [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
FTRs Forward Price Range	(2.36)		(4.12)
FTRs [Member] \| High [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
FTRs Forward Price Range	4.11		7.76
Measured On A Recurring Basis [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Asset Description
Institutional money market funds	0		0
FTR assets	0		0
Total Assets	0		0
Liability Description
Long-term debt	0		0
FTR liabilities	0		0
Total Liabilities	0		0
Measured On A Recurring Basis [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Asset Description
Institutional money market funds	67,411,000		63,701,000
FTR assets	0		0
Total Assets	67,411,000		63,701,000
Liability Description
Long-term debt	1,587,097,000		1,601,816,000
FTR liabilities	0		0
Total Liabilities	1,587,097,000		1,601,816,000
Measured On A Recurring Basis [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Asset Description
Institutional money market funds	0		0
FTR assets	2,245,000		10,776,000
Total Assets	2,245,000		10,776,000
Liability Description
Long-term debt	0		0
FTR liabilities	432,000		827,000
Total Liabilities	432,000		827,000
Measured On A Recurring Basis [Member] \| Cleco Power [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Asset Description
Institutional money market funds	0		0
FTR assets	0		0
Total Assets	0		0
Liability Description
Long-term debt	0		0
FTR liabilities	0		0
Total Liabilities	0		0
Measured On A Recurring Basis [Member] \| Cleco Power [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Asset Description
Institutional money market funds	65,890,000		58,680,000
FTR assets	0		0
Total Assets	65,890,000		58,680,000
Liability Description
Long-term debt	1,525,097,000		1,544,816,000
FTR liabilities	0		0
Total Liabilities	1,525,097,000		1,544,816,000
Measured On A Recurring Basis [Member] \| Cleco Power [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Asset Description
Institutional money market funds	0		0
FTR assets	2,245,000		10,776,000
Total Assets	2,245,000		10,776,000
Liability Description
Long-term debt	0		0
FTR liabilities	432,000		827,000
Total Liabilities	$ 432,000		$ 827,000

Amount of transfers of assets and liabilities measured on a recurring basis of fair value hierarchy Levels.

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Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Deferred Fuel

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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- Definition

The forward price on the price risk forward or futures contract, such as a gas futures contract.

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- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: 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 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph a, f, g

-Article 7

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560

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Fair value of financial and nonfinancial obligations.

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- Definition

The fair value amount of long-term debt 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.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of price risk derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets on the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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Fair value as of the balance sheet date of price risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities on the balance sheet.

+ References

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