Leases - Supplemental Balance Sheet and Cash Flow Information and Other Supplemental Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
ROU assets
Operating	$ 26,172	$ 28,791
Finance	13,720	14,840
Total ROU assets	39,892	43,631
Current lease liabilities
Operating	2,802	2,978
Finance	682	617
Non-current lease liabilities
Operating	23,333	25,779
Finance	14,562	15,244
Total lease liabilities	41,379	44,618
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	4,504	4,452
Operating cash flows from finance leases	1,587	1,646
Financing cash flows from finance leases	617	557
ROU assets obtained in exchange for new lease liabilities	$ 0	$ 15,881
Operating leases
Weighted average remaining lease term (in years)	9 years 10 months 24 days	10 years 9 months 18 days
Weighted-average discount rate	4.31%	4.31%
Finance leases
Weighted average remaining lease term (in years)	12 years 3 months 18 days	13 years 3 months 18 days
Weighted-average discount rate	10.18%	10.18%
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesCurrent	us-gaap:OtherLiabilitiesCurrent
CLECO POWER
ROU assets
Operating	$ 26,006	$ 28,633
Finance	13,720	14,840
Total ROU assets	39,726	43,473
Current lease liabilities
Operating	2,672	2,935
Finance	682	617
Non-current lease liabilities
Operating	23,295	25,658
Finance	14,562	15,244
Total lease liabilities	41,211	44,454
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	4,120	4,203
Operating cash flows from finance leases	1,587	1,646
Financing cash flows from finance leases	617	557
ROU assets obtained in exchange for new lease liabilities	$ 0	$ 15,749
Operating leases
Weighted average remaining lease term (in years)	10 years	10 years 9 months 18 days
Weighted-average discount rate	4.31%	4.31%
Finance leases
Weighted average remaining lease term (in years)	12 years 3 months 18 days	13 years 3 months 18 days
Weighted-average discount rate	10.18%	10.18%