Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Accumulated other comprehensive loss [Roll Forward]
Balances	$ 2,046,763
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	(2,191)
Balances	2,021,909
Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	1,500
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	(2,191)
Balances	(691)
Cleco Power [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	1,535,202
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	(367)	$ 253
Balances	1,517,689
Cleco Power [Member] \| Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	(13,422)	(17,092)
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	(584)
Amounts reclassified from accumulated other comprehensive income, net of tax	164	200
Net current-period other comprehensive income	(367)	253
Balances	(13,789)	(16,839)
Cleco Power [Member] \| Total AOCI [Member] \| Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax	53	53
Cleco Power [Member] \| Postretirement Benefit Net Loss [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	(7,905)	(11,364)
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	(584)
Amounts reclassified from accumulated other comprehensive income, net of tax	164	200
Net current-period other comprehensive income	(420)	200
Balances	(8,325)	(11,164)
Cleco Power [Member] \| Net Loss on Cash Flow Hedges [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	(5,517)	(5,728)
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	53	53
Balances	(5,464)	(5,675)
Cleco Power [Member] \| Net Loss on Cash Flow Hedges [Member] \| Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax	53	53
Predecessor [Member]
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income		581
Predecessor [Member] \| Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		(26,585)
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		528
Net current-period other comprehensive income		581
Balances		(26,004)
Predecessor [Member] \| Total AOCI [Member] \| Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		53
Predecessor [Member] \| Postretirement Benefit Net Loss [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		(20,857)
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		528
Net current-period other comprehensive income		528
Balances		(20,329)
Predecessor [Member] \| Net Loss on Cash Flow Hedges [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances		(5,728)
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income		53
Balances		(5,675)
Predecessor [Member] \| Net Loss on Cash Flow Hedges [Member] \| Interest Expense [Member]
Net current-period other comprehensive income [Abstract]
Amounts reclassified from accumulated other comprehensive income, net of tax		$ 53
Successor [Member]
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	(2,191)
Successor [Member] \| Total AOCI [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	1,500
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	(2,065)
Amounts reclassified from accumulated other comprehensive income, net of tax	(126)
Net current-period other comprehensive income	(2,191)
Balances	(691)
Successor [Member] \| Postretirement Benefit Net Loss [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	1,500
Net current-period other comprehensive income [Abstract]
Postretirement benefit adjustments during the period	(2,065)
Amounts reclassified from accumulated other comprehensive income, net of tax	(126)
Net current-period other comprehensive income	(2,191)
Balances	(691)
Successor [Member] \| Net Loss on Cash Flow Hedges [Member]
Accumulated other comprehensive loss [Roll Forward]
Balances	0
Net current-period other comprehensive income [Abstract]
Net current-period other comprehensive income	0
Balances	$ 0

Amount of ownership interest in a limited liability company (LLC), including portions attributable to both the parent and noncontrolling interests.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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