Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2020

Entity Information [Line Items]

Schedule of Net Periodic Benefit Cost / (Income)

The net periodic benefit cost of the pension benefit plans for the three months ended March 31, 2020 and 2019 was:

	Three months ended
	March 31,
$ in millions	2020			2019
Service cost	$	0.9		$	0.9
Interest cost	3.0			3.7
Expected return on plan assets	(4.7		)	(5.0		)
Amortization of unrecognized:
Prior service cost	0.3			0.3
Actuarial loss	1.5			1.1
Net periodic benefit cost	$	1.0		$	1.0

THE DAYTON POWER AND LIGHT COMPANY [Member]

Entity Information [Line Items]

Schedule of Net Periodic Benefit Cost / (Income)

The net periodic benefit cost of the pension benefit plans for the three months ended March 31, 2020 and 2019 was:

	Three months ended
	March 31,
$ in millions	2020			2019
Service cost	$	0.9		$	0.9
Interest cost	3.0			3.7
Expected return on plan assets	(4.7		)	(5.0		)
Amortization of unrecognized:
Prior service cost	0.3			0.5
Actuarial loss	2.2			1.7
Net periodic benefit cost	$	1.7		$	1.8