Regulatory Assets and Liabilities - Schedule of Regulatory Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Regulatory Assets [Line Items]
Total regulatory assets, net	$ 293,504	$ 307,374
Cleco Holdings | Fair value of long-term debt
Regulatory Assets [Line Items]
Regulatory assets	136,589	138,701
Cleco Holdings | Postretirement costs
Regulatory Assets [Line Items]
Regulatory assets	18,891	19,387
Cleco Holdings | Financing costs
Regulatory Assets [Line Items]
Regulatory assets	8,193	8,279
Cleco Holdings | Debt issuance costs
Regulatory Assets [Line Items]
Regulatory assets	6,149	6,252
CLECO POWER
Regulatory Assets [Line Items]
Total regulatory assets, net	123,682	134,755
CLECO POWER | Mining costs
Regulatory Assets [Line Items]
Regulatory assets	637	1,274
CLECO POWER | Interest costs
Regulatory Assets [Line Items]
Regulatory assets	4,146	4,208
CLECO POWER | AROs
Regulatory Assets [Line Items]
Regulatory assets	3,238	3,099
CLECO POWER | Postretirement costs
Regulatory Assets [Line Items]
Regulatory assets	138,388	140,245
CLECO POWER | Tree trimming costs
Regulatory Assets [Line Items]
Regulatory assets	9,463	9,069
CLECO POWER | Training costs
Regulatory Assets [Line Items]
Regulatory assets	6,358	6,396
CLECO POWER | Surcredits, net
Regulatory Assets [Line Items]
Regulatory assets	289	289
CLECO POWER | AMI deferred revenue requirement
Regulatory Assets [Line Items]
Regulatory assets	3,545	3,681
CLECO POWER | Emergency declarations
Regulatory Assets [Line Items]
Regulatory assets	2,560	2,980
CLECO POWER | Production operations and maintenance expenses
Regulatory Assets [Line Items]
Regulatory assets	11,458	12,245
CLECO POWER | AFUDC equity gross-up
Regulatory Assets [Line Items]
Regulatory assets	72,622	71,952
CLECO POWER | Acquisition/ transaction costs
Regulatory Assets [Line Items]
Regulatory assets	2,204	2,230
CLECO POWER | Acquisition/ transaction costs | Coughlin transaction costs
Regulatory Assets [Line Items]
Regulatory assets	930	938
CLECO POWER | Financing costs
Regulatory Assets [Line Items]
Regulatory assets	7,830	7,923
CLECO POWER | Corporate franchise tax, net
Regulatory Assets [Line Items]
Regulatory assets		1,416
CLECO POWER | Non-service cost of postretirement benefits
Regulatory Assets [Line Items]
Regulatory assets	5,925	4,629
CLECO POWER | Energy efficiency
Regulatory Assets [Line Items]
Regulatory assets		2,585
CLECO POWER | Accumulated deferred fuel
Regulatory Assets [Line Items]
Regulatory assets	$ 17,179	$ 20,112