Income Taxes Income Taxes, Income Tax Examination (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Feb. 28, 2011	Dec. 31, 2010
Internal Revenue Service (IRS) [Member]
Summary of income tax examinations [Abstract]
Deposits with IRS	$ 60.4	$ 8.2	$ 52.2
Amounts deposited with IRS- remaining amount to offset tax and interest liabilities	43.2
Maximum decrease in unrecognized tax benefits as a result of settlement with the IRS	11.0
Cleco Power [Member] | Internal Revenue Service (IRS) [Member]
Summary of income tax examinations [Abstract]
Maximum decrease in unrecognized tax benefits as a result of settlement with the IRS	$ 11.3
Minimum [Member] | Internal Revenue Service (IRS) [Member]
Summary of income tax examinations [Abstract]
Income Tax Years That Are Subject To Examination	2001
Income tax years that are under examination	2001
Minimum [Member] | State and Local Jurisdiction [Member]
Summary of income tax examinations [Abstract]
Income Tax Years That Are Subject To Examination	2001
Maximum [Member] | Internal Revenue Service (IRS) [Member]
Summary of income tax examinations [Abstract]
Income Tax Years That Are Subject To Examination	2011
Income tax years that are under examination	2009
Maximum [Member] | State and Local Jurisdiction [Member]
Summary of income tax examinations [Abstract]
Income Tax Years That Are Subject To Examination	2011