Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2023

Schedule of Regulatory Assets and Liabilities [Table Text Block]

The following table presents DPL’s Regulatory assets and liabilities:

	Type of Recovery	Amortization Through	December 31,
$ in millions			2023		2022
Regulatory assets, current:
Undercollections to be collected through rate riders	A/B	2024	$	51.7	$	38.7
Uncollectible expense being recovered in base rates	B	2024	1.7		—
Vegetation management being recovered in base rates	B	2024	2.7		—
Rate case expenses being recovered in base rates	B	2024	0.5		0.5
Total regulatory assets, current			56.6		39.2
Regulatory assets, non-current:
Pension benefits	A/B	Ongoing	62.6		64.2
Regulatory compliance costs	A	2028	45.0		6.4
Energy efficiency	D	Undetermined	4.1		—
Smart grid and AMI costs	B/C	Ongoing	3.2		2.3
Unamortized loss on reacquired debt	B	Ongoing	1.1		2.0
Deferred storm costs	B	Ongoing	2.2		8.7
Deferred rate case costs	B	2028	1.5		1.9
Deferred vegetation management	B	2028	19.9		21.9
CIS replacement	D	Undetermined	3.1		1.1
Transmission formula rate debits	B	2025	6.7		—
Decoupling deferral	A	2028	—		13.8
Uncollectible deferral	B	2028	6.3		7.5
Total regulatory assets, non-current			155.7		129.8
Total regulatory assets			$	212.3	$	169.0
Regulatory liabilities, current:
Overcollection of costs to be refunded through rate riders	A/B	2024	$	14.7	$	27.6
Transmission formula rate credits	B	2024	3.3		12.8
Total regulatory liabilities, current			18.0		40.4
Regulatory liabilities, non-current:
Estimated costs of removal - regulated property		Not Applicable	134.2		136.8
Deferred income taxes payable through rates		Ongoing	42.6		45.2
TCJA regulatory liability	B	Ongoing	1.0		4.5
Transmission formula rate credits	B	2024	—		5.4
PJM transmission enhancement settlement	B	2025	1.7		3.5
Postretirement benefits	B	Ongoing	2.6		3.3
Total regulatory liabilities, non-current			182.1		198.7
Total regulatory liabilities			$	200.1	$	239.1

A – Recovery of incurred costs plus rate of return.

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

C – Includes costs associated with Smart Grid Phase 2 development for which recovery is not yet determined but is considered probable of occurring in future rate proceedings.

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

Subsidiaries [Member]

Schedule of Regulatory Assets and Liabilities [Table Text Block]

The following table presents AES Ohio’s Regulatory assets and liabilities:

	Type of Recovery	Amortization Through	December 31,
$ in millions			2023		2022
Regulatory assets, current:
Undercollections to be collected through rate riders	A/B	2024	$	51.7	$	38.7
Uncollectible expense being recovered in base rates	B	2024	1.7		—
Vegetation management being recovered in base rates	B	2024	2.7		—
Rate case expenses being recovered in base rates	B	2024	0.5		0.5
Total regulatory assets, current			56.6		39.2
Regulatory assets, non-current:
Pension benefits	A/B	Ongoing	62.6		64.2
Regulatory compliance costs	A	2028	45.0		6.4
Energy efficiency	D	Undetermined	4.1		—
Smart grid and AMI costs	B/C	Ongoing	3.2		2.3
Unamortized loss on reacquired debt	B	Ongoing	1.1		2.0
Deferred storm costs	B	Ongoing	2.2		8.7
Deferred rate case costs	B	2028	1.5		1.9
Deferred vegetation management	B	2028	19.9		21.9
CIS replacement	D	Undetermined	3.1		1.1
Transmission formula rate debits	B	2025	6.7		—
Decoupling deferral	A	2028	—		13.8
Uncollectible deferral	B	2028	6.3		7.5
Total regulatory assets, non-current			155.7		129.8
Total regulatory assets			$	212.3	$	169.0
Regulatory liabilities, current:
Overcollection of costs to be refunded through rate riders	A/B	2024	$	14.7	$	27.6
Transmission formula rate credits	B	2024	3.3		12.8
Total regulatory liabilities, current			18.0		40.4
Regulatory liabilities, non-current:
Estimated costs of removal - regulated property		Not Applicable	134.2		136.8
Deferred income taxes payable through rates		Ongoing	42.6		45.2
TCJA regulatory liability	B	Ongoing	1.0		4.5
Transmission formula rate credits	B	2024	—		5.4
PJM transmission enhancement settlement	B	2025	1.7		3.5
Postretirement benefits	B	Ongoing	2.6		3.3
Total regulatory liabilities, non-current			182.1		198.7
Total regulatory liabilities			$	200.1	$	239.1

A – Recovery of incurred costs plus rate of return.

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

C – Includes costs associated with Smart Grid Phase 2 development for which recovery is not yet determined but is considered probable of occurring in future rate proceedings.

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