Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2019

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, 2019 and 2018 was:

	Three months ended
	March 31,
$ in millions	2019			2018
Service cost	$	0.9		$	1.5
Interest cost	3.7			3.4
Expected return on plan assets	(5.0		)	(5.2		)
Amortization of unrecognized:
Prior service cost	0.3			0.2
Actuarial loss	1.1			1.6
Net periodic benefit cost	$	1.0		$	1.5

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, 2019 and 2018 was:

	Three months ended
	March 31,
$ in millions	2019			2018
Service cost	$	0.9		$	1.5
Interest cost	3.7			3.4
Expected return on plan assets	(5.0		)	(5.2		)
Amortization of unrecognized:
Prior service cost	0.5			0.4
Actuarial loss	1.7			2.3
Net periodic benefit cost	$	1.8		$	2.4