Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Long-Term Purchase Obligations (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
FUTURE PAYMENTS UNDER LONG-TERM PURCHASE OBLIGATIONS
2021	$ 45,958,000
2022	24,307,000
2023	9,906,000
2024	8,491,000
2025	9,512,000
Thereafter	10,869,000
Total long-term purchase obligations	109,043,000
Payments under long-term purchase obligations	92,500,000	$ 94,800,000	$ 70,500,000
CLECO POWER
FUTURE PAYMENTS UNDER LONG-TERM PURCHASE OBLIGATIONS
2021	20,991,000
2022	21,279,000
2023	8,747,000
2024	7,984,000
2025	7,931,000
Thereafter	16,515,000
Total long-term purchase obligations	83,447,000
Payments under long-term purchase obligations	24,800,000	$ 35,300,000	$ 60,700,000
Cleco Holdings \| Purchase of coal, petroleum coke, limestone, entergy capacity and energy delivery facilities
FUTURE PAYMENTS UNDER LONG-TERM PURCHASE OBLIGATIONS
Total long-term purchase obligations	$ 0

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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The amount purchased during the period under an unrecorded unconditional purchase obligation (for example, under the take-or-pay or throughput contract).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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