Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2018

Subsidiaries [Member]

Schedule of Regulatory Assets and Liabilities [Table Text Block]

The following table presents DP&L’s Regulatory assets and liabilities:

	Type of Recovery	Amortization Through	December 31,
$ in millions			2018		2017
Regulatory assets, current:
Undercollections to be collected through rate riders	A/B	2019	$	40.5	$	23.9
Rate case expenses being recovered in base rates	B	2019	0.6		—
Total regulatory assets, current			41.1		23.9
Regulatory assets, non-current:
Pension benefits	B	Ongoing	87.5		92.4
Unrecovered OVEC charges	C	Undetermined	28.7		27.8
Fuel costs	B	2020	3.3		9.3
Regulatory compliance costs	B	2020	6.1		9.2
Smart grid and AMI costs	B	Undetermined	8.5		7.3
Unamortized loss on reacquired debt	B	Various	6.0		7.0
Deferred storm costs	A	Undetermined	4.7		2.1
Deferred vegetation management and other	A/B	Undetermined	7.8		8.1
Total regulatory assets, non-current			152.6		163.2
Total regulatory assets			$	193.7	$	187.1
Regulatory liabilities, current:
Overcollection of costs to be refunded through rate riders	A/B	2018	$	34.9	$	14.8
Total regulatory liabilities, current			34.9		14.8
Regulatory liabilities, non-current:
Estimated costs of removal - regulated property		Not Applicable	139.1		132.8
Deferred income taxes payable through rates		Various	116.3		83.4
PJM transmission enhancement settlement	A	2025	16.9		—
Postretirement benefits	B	Ongoing	6.0		5.0
Total regulatory liabilities, non-current			278.3		221.2
Total regulatory liabilities			$	313.2	$	236.0

A – Recovery of incurred costs plus rate of return.

B – Recovery of incurred costs without a rate of return.

C – Recovery not yet determined, but recovery is probable of occurring in future rate proceedings.