Fair Value Accounting - Amount of Gain (Loss) Recognized in Income on Derivatives (Details) - DERIVATIVES NOT DESIGNATED AS HEDGING INSTRUMENTS - Commodity-related contracts - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Commodity-related contracts
Net gain (loss) recognized in income on derivatives	$ (5,826)	$ (6,093)
Accumulated deferred fuel
Commodity-related contracts
Unrealized gains (losses) associated with FTRs		(1,300)
Accumulated deferred fuel \| Maximum
Commodity-related contracts
Unrealized gains (losses) associated with FTRs	(100)
CLECO POWER
Commodity-related contracts
Net gain (loss) recognized in income on derivatives	262	645
CLECO POWER \| Accumulated deferred fuel
Commodity-related contracts
Unrealized gains (losses) associated with FTRs		(1,300)
CLECO POWER \| Accumulated deferred fuel \| Maximum
Commodity-related contracts
Unrealized gains (losses) associated with FTRs	(100)
Electric operations
Commodity-related contracts
Gain recognized in income on derivatives	7,444	1,396
Electric operations \| CLECO POWER
Commodity-related contracts
Gain recognized in income on derivatives	7,444	1,396
Purchased power
Commodity-related contracts
Loss recognized in income on derivatives	(8,560)	(381)
Purchased power \| CLECO POWER
Commodity-related contracts
Loss recognized in income on derivatives	(7,182)	(751)
Fuel used for electric generation
Commodity-related contracts
Loss recognized in income on derivatives	$ (4,710)	$ (7,108)

The amount of unrealized gains (losses) from the net mark-to-market impact relating to open natural gas positions or FTRs.

No definition available.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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Amount of increase in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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