Fair Value Accounting - Amount of Gain (Loss) Recognized in Income on Derivatives (Details) - DERIVATIVES NOT DESIGNATED AS HEDGING INSTRUMENTS - Price Risk Derivative - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Commodity-related contracts
Net gain (loss) recognized in income on derivatives	$ (6,093)	$ 1,885
Accumulated deferred fuel
Commodity-related contracts
Unrealized losses associated with FTRs	1,300	2,900
Electric operations
Commodity-related contracts
Gain recognized in income on derivatives	1,396	5,209
Purchased power
Commodity-related contracts
Loss recognized in income on derivatives	(381)	(3,324)
Fuel used for electric generation
Commodity-related contracts
Loss recognized in income on derivatives	(7,108)	0
CLECO POWER
Commodity-related contracts
Net gain (loss) recognized in income on derivatives	645	3,223
CLECO POWER \| Accumulated deferred fuel
Commodity-related contracts
Unrealized losses associated with FTRs	1,300	2,900
CLECO POWER \| Electric operations
Commodity-related contracts
Gain recognized in income on derivatives	1,396	5,206
CLECO POWER \| Purchased power
Commodity-related contracts
Loss recognized in income on derivatives	$ (751)	$ (1,983)

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=109980867&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=109980867&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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- References

No definition available.

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