Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2017

The net periodic benefit cost of the pension benefit plans for the three months ended March 31, 2017 and 2016 was:



Net Periodic Benefit Cost	Pension
	Three months ended
	March 31,
$ in millions	2017			2016
Service cost	$	1.4		$	1.4
Interest cost	3.6			3.7
Expected return on plan assets	(5.7		)	(5.7		)
Plan curtailment ^(a)	4.1			—
Amortization of unrecognized:
Prior service cost	0.4			0.5
Actuarial loss	1.3			1.0
Net periodic benefit cost	$	5.1		$	0.9


(a)	As a result of the decision to retire certain of DP&L's coal-fired plants, we recognized a plan curtailment of $4.1 million in the first quarter of 2017. See Note 14 – Fixed-asset Impairment for more information.

Benefit payments, which reflect future service, are estimated to be paid as follows:



$ in millions
Estimated to be paid during the twelve months ending March 31,	Pension
2018	$	18.8
2019	25.5
2020	26.0
2021	26.4
2022	26.7
2023 - 2027	139.6

The net periodic benefit cost of the pension benefit plans for the three months ended March 31, 2017 and 2016 was:



Net Periodic Benefit Cost	Pension
	Three months ended
	March 31,
$ in millions	2017			2016
Service cost	$	1.4		$	1.4
Interest cost	3.6			3.7
Expected return on plan assets	(5.7		)	(5.7		)
Plan curtailment ^(a)	5.6			—
Amortization of unrecognized:
Prior service cost	0.5			0.8
Actuarial loss	2.2			1.8
Net periodic benefit cost	$	7.6		$	2.0


(a)	As a result of the decision to retire certain of DP&L's coal-fired plants, we recognized a plan curtailment of $5.6 million in the first quarter of 2017. See Note 14 – Fixed-asset Impairment for more information.

Benefit payments, which reflect future service, are estimated to be paid as follows:



$ in millions
Estimated to be paid during the twelve months ending March 31,	Pension
2018	$	18.8
2019	25.5
2020	26.0
2021	26.4
2022	26.7
2023 - 2027	139.6