Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2015

Pension And Postretirement Benefit Plans' Obligations And Assets

The following tables set forth the changes in our pension and postemployment benefit plans’ obligations and assets recorded on the balance sheets at December 31, 2015 and 2014. The amounts presented in the following tables for pension obligations include the collective bargaining plan formula, traditional management plan formula and cash balance plan formula and the SERP in the aggregate. The amounts presented for postemployment obligations include both health and life insurance benefits.

$ in millions	Pension
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at January 1	$	443.8		$	370.5
Service cost	7.1			5.9
Interest cost	17.3			17.5
Plan amendments	—			6.8
Actuarial (gain) / loss	(34.5		)	67.3
Benefits paid	(22.9		)	(24.2		)
Benefit obligation at December 31	410.8			443.8
Change in plan assets
Fair value of plan assets at January 1	371.7			349.1
Actual return on plan assets	(8.8		)	46.4
Contributions to plan assets	5.4			0.4
Benefits paid	(22.9		)	(24.2		)
Fair value of plan assets at December 31	345.4			371.7
Funded status of plan	$	(65.4	)	$	(72.1	)
	December 31,
Amounts recognized in the Balance sheets	2015			2014
Current liabilities	$	(0.4	)	$	(0.4	)
Non-current liabilities	(65.0		)	(71.7		)
Net liability at December 31,	$	(65.4	)	$	(72.1	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	12.0		$	14.1
Net actuarial loss	94.7			103.4
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	106.7		$	117.5
Recorded as:
Regulatory asset	$	91.1		$	99.0
Regulatory liability	—			—
Accumulated other comprehensive income	15.6			18.5
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	106.7		$	117.5

$ in millions	Postretirement
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at beginning of period	$	19.6		$	19.7
Service cost	0.2			0.2
Interest cost	0.6			0.8
Actuarial (gain) / loss	(1.1		)	0.2
Benefits paid	(1.5		)	(1.3		)
Benefit obligation at end of period	17.8			19.6
Change in plan assets
Fair value of plan assets at beginning of period	3.3			3.7
Contributions to plan assets	1.0			0.9
Benefits paid	(1.5		)	(1.3		)
Fair value of plan assets at end of period	2.8			3.3
Funded status of plan	$	(15.0	)	$	(16.3	)
	December 31,
	2015			2014
Amounts recognized in the Balance sheets
Current liabilities	$	(0.4	)	$	(0.5	)
Non-current liabilities	(14.6		)	(15.8		)
Net liability at December 31,	$	(15.0	)	$	(16.3	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	0.3		$	0.4
Net actuarial gain	(5.5		)	(5.0		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.2	)	$	(4.6	)
Recorded as:
Regulatory asset	$	0.3		$	0.4
Regulatory liability	(5.1		)	(4.8		)
Accumulated other comprehensive income	(0.4		)	(0.2		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.2	)	$	(4.6	)

Schedule of Amounts Recognized in Balance Sheet

The following tables set forth the changes in our pension and postemployment benefit plans’ obligations and assets recorded on the balance sheets at December 31, 2015 and 2014. The amounts presented in the following tables for pension obligations include the collective bargaining plan formula, traditional management plan formula and cash balance plan formula and the SERP in the aggregate. The amounts presented for postemployment obligations include both health and life insurance benefits.

$ in millions	Pension
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at January 1	$	443.8		$	370.5
Service cost	7.1			5.9
Interest cost	17.3			17.5
Plan amendments	—			6.8
Actuarial (gain) / loss	(34.5		)	67.3
Benefits paid	(22.9		)	(24.2		)
Benefit obligation at December 31	410.8			443.8
Change in plan assets
Fair value of plan assets at January 1	371.7			349.1
Actual return on plan assets	(8.8		)	46.4
Contributions to plan assets	5.4			0.4
Benefits paid	(22.9		)	(24.2		)
Fair value of plan assets at December 31	345.4			371.7
Funded status of plan	$	(65.4	)	$	(72.1	)
	December 31,
Amounts recognized in the Balance sheets	2015			2014
Current liabilities	$	(0.4	)	$	(0.4	)
Non-current liabilities	(65.0		)	(71.7		)
Net liability at December 31,	$	(65.4	)	$	(72.1	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	12.0		$	14.1
Net actuarial loss	94.7			103.4
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	106.7		$	117.5
Recorded as:
Regulatory asset	$	91.1		$	99.0
Regulatory liability	—			—
Accumulated other comprehensive income	15.6			18.5
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	106.7		$	117.5

$ in millions	Postretirement
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at beginning of period	$	19.6		$	19.7
Service cost	0.2			0.2
Interest cost	0.6			0.8
Actuarial (gain) / loss	(1.1		)	0.2
Benefits paid	(1.5		)	(1.3		)
Benefit obligation at end of period	17.8			19.6
Change in plan assets
Fair value of plan assets at beginning of period	3.3			3.7
Contributions to plan assets	1.0			0.9
Benefits paid	(1.5		)	(1.3		)
Fair value of plan assets at end of period	2.8			3.3
Funded status of plan	$	(15.0	)	$	(16.3	)
	December 31,
	2015			2014
Amounts recognized in the Balance sheets
Current liabilities	$	(0.4	)	$	(0.5	)
Non-current liabilities	(14.6		)	(15.8		)
Net liability at December 31,	$	(15.0	)	$	(16.3	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	0.3		$	0.4
Net actuarial gain	(5.5		)	(5.0		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.2	)	$	(4.6	)
Recorded as:
Regulatory asset	$	0.3		$	0.4
Regulatory liability	(5.1		)	(4.8		)
Accumulated other comprehensive income	(0.4		)	(0.2		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.2	)	$	(4.6	)

Schedule of Net Periodic Benefit Cost / (Income)

The net periodic benefit cost of the pension and postretirement plans were:

Net Periodic Benefit Cost - Pension
	Years ended December 31,
$ in millions	2015			2014			2013
Service cost	$	7.1		$	5.9		$	7.2
Interest cost	17.3			17.5			15.6
Expected return on assets (a)	(22.6		)	(22.9		)	(23.3		)
Amortization of unrecognized:
Actuarial gain	5.8			3.4			4.9
Prior service cost	2.0			1.5			1.5
Net periodic benefit cost	$	9.6		$	5.4		$	5.9

Net Periodic Benefit Cost - Postretirement
	Years ended December 31,
$ in millions	2015			2014			2013
Service cost	$	0.2		$	0.2		$	0.2
Interest cost	0.6			0.8			0.8
Expected return on assets (a)	(0.1		)	(0.2		)	(0.1		)
Amortization of unrecognized:
Actuarial loss	(0.6		)	(0.6		)	(0.5		)
Prior service cost	0.1			—			—
Net periodic benefit cost	$	0.2		$	0.2		$	0.4

Other Changes in Plan Assets and Benefit Obligation Recognized in Accumulated Other Comprehensive Income, Regulatory Assets And Regulatory Liabilities

Pension
	Years ended December 31,
$ in millions	2015			2014			2013
Net actuarial loss / (gain)	$	(3.0	)	$	43.8		$	(12.0	)
Prior service cost	—			6.8			—
Reversal of amortization item:
Net actuarial loss	(5.8		)	(3.4		)	(4.9		)
Prior service cost	(2.0		)	(1.5		)	(1.5		)
Total recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(10.8	)	$	45.7		$	(18.4	)
Total recognized in net periodic benefit cost and Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(1.2	)	$	51.1		$	(12.5	)

Postretirement
	Years ended December 31,
$ in millions	2015			2014		2013
Net actuarial loss / (gain)	$	(1.1	)	$	0.4	$	(2.0	)
Reversal of amortization item:
Net actuarial gain	0.6			0.6		0.5
Prior service cost	$	(0.1	)	$	—	$	—
Total recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(0.6	)	$	1.0	$	(1.5	)
Total recognized in net periodic benefit cost and Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(0.4	)	$	1.2	$	(1.1	)

Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income, Regulatory Assets And Regulatory Liabilities

Estimated amounts that will be amortized from AOCI, Regulatory assets and Regulatory liabilities into net periodic benefit costs during 2016 are:

$ in millions	Pension		Postretirement
Actuarial gain / (loss)	$	4.3	$	(0.6	)
Prior service cost	$	1.9	$	0.1

Weighted Average Assumptions Used to Determine Benefit Obligations

The weighted average assumptions used to determine benefit obligations at December 31, 2015, 2014 and 2013 were:

Benefit Obligation Assumptions	Pension			Postretirement
	2015	2014	2013	2015	2014	2013
Discount rate for obligations	4.49%	4.02%	4.86%	4.10%	3.71%	4.58%
Rate of compensation increases	3.94%	3.94%	3.94%	N/A	N/A	N/A

Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost (Income)

The weighted-average assumptions used to determine net periodic benefit cost (income) for the years ended December 31, 2015, 2014 and 2013 were:

Net Periodic Benefit Cost / (Income) Assumptions	Pension			Postretirement
	2015	2014	2013	2015	2014	2013
Discount rate	4.02%	4.86%	4.04%	3.81%	4.51%	4.58%
Expected rate of return on plan assets	6.50%	6.75%	6.75%	4.50%	6.00%	6.00%
Rate of compensation increases	3.94%	3.94%	3.94%	N/A	N/A	N/A

Assumed Health Care Cost Trend Rates

The assumed health care cost trend rates at December 31, 2015, 2014 and 2013 are as follows:

Health Care Cost Assumptions	Expense			Benefit Obligation
	2015	2014	2013	2015	2014	2013
Pre - age 65
Current health care cost trend rate	6.97%	7.75%	8.00%	6.85%	6.97%	7.75%
Year trend reaches ultimate	2029	2023	2019	2036	2029	2023
Post - age 65
Current health care cost trend rate	6.97%	6.75%	7.50%	6.85%	6.97%	6.75%
Year trend reaches ultimate	2029	2021	2018	2036	2029	2021
Ultimate health care cost trend rate	4.50%	5.00%	5.00%	4.50%	4.50%	5.00%

Effect of Change in Health Care Cost Trend Rate

A one-percentage point change in assumed health care cost trend rates would have the following effects on the net periodic postemployment benefit cost and the accumulated postemployment benefit obligation:

Effect of change in health care cost trend rate
$ in millions	One-percent increase		One-percent decrease
Service cost plus interest cost	$	0.1	$	—
Benefit obligation	$	0.8	$	(0.7	)

Schedule of Allocation of Plan Assets

The following table summarizes our target pension plan allocation for 2015:

		Percentage of plan assets as of December 31,
Asset category	Long-Term Mid-Point Target Allocation	2015	2014
Equity Securities	28%	17%	18%
Debt Securities	72%	67%	69%
Real Estate	—%	9%	7%
Other	—%	7%	6%

Estimated Future Benefit Payments and Medicare Part D Reimbursements

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

Estimated future benefit payments and Medicare Part D reimbursements
$ in millions due within the following years:	Pension		Postretirement
2016	$	24.6	$	1.7
2017	$	25.2	$	1.6
2018	$	25.8	$	1.5
2019	$	26.3	$	1.4
2020	$	26.7	$	1.4
2021 - 2025	$	134.8	$	5.7

THE DAYTON POWER AND LIGHT COMPANY [Member]

Schedule of Amounts Recognized in Balance Sheet

December 31, 2015 and 2014. The amounts presented in the following tables for pension obligations include the collective bargaining plan formula, traditional management plan formula and cash balance plan formula and the SERP in the aggregate. The amounts presented for postemployment obligations include both health and life insurance benefits.

$ in millions	Pension
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at beginning of period	$	443.8		$	370.5
Service cost	7.1			5.9
Interest cost	17.3			17.5
Plan amendments	—			6.8
Actuarial (gain) / loss	(34.5		)	67.3
Benefits paid	(22.9		)	(24.2		)
Benefit obligation at end of period	410.8			443.8
Change in plan assets
Fair value of plan assets at beginning of period	371.7			349.1
Actual return on plan assets	(8.8		)	46.4
Contributions to plan assets	5.4			0.4
Benefits paid	(22.9		)	(24.2		)
Fair value of plan assets at end of period	345.4			371.7
Funded status of plan	$	(65.4	)	$	(72.1	)
	December 31,
	2015			2014
Amounts recognized in the Balance sheets
Current liabilities	$	(0.4	)	$	(0.4	)
Non-current liabilities	(65.0		)	(71.7		)
Net liability at Year ended December 31,	$	(65.4	)	$	(72.1	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	17.0		$	20.3
Net actuarial loss / (gain)	139.7			152.5
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	156.7		$	172.8
Recorded as:
Regulatory asset	$	91.1		$	99.0
Regulatory liability	—			—
Accumulated other comprehensive income	65.6			73.8
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	156.7		$	172.8

$ in millions	Postretirement
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at beginning of period	$	19.6		$	19.7
Service cost	0.2			0.2
Interest cost	0.6			0.8
Actuarial (gain) / loss	(1.1		)	0.2
Benefits paid	(1.5		)	(1.3		)
Benefit obligation at end of period	17.8			19.6
Change in plan assets
Fair value of plan assets at beginning of period	3.3			3.7
Contributions to plan assets	1.0			0.9
Benefits paid	(1.5		)	(1.3		)
Fair value of plan assets at end of period	2.8			3.3
Funded status of plan	$	(15.0	)	$	(16.3	)
	December 31,
	2015			2014
Amounts recognized in the Balance sheets
Current liabilities	$	(0.4	)	$	(0.5	)
Non-current liabilities	(14.6		)	(15.8		)
Net liability at Year ended December 31,	$	(15.0	)	$	(16.3	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	0.5		$	0.6
Net actuarial loss / (gain)	(6.2		)	(5.8		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.7	)	$	(5.2	)
Recorded as:
Regulatory asset	$	0.3		$	—
Regulatory liability	(5.1		)	(4.5		)
Accumulated other comprehensive income	(0.9		)	(0.7		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.7	)	$	(5.2	)

Schedule of Net Periodic Benefit Cost / (Income)

The net periodic benefit cost of the pension and postretirement plans were:

Net Periodic Benefit Cost - Pension
	Years ended December 31,
$ in millions	2015			2014			2013
Service cost	$	7.1		$	5.9		$	7.2
Interest cost	17.3			17.5			15.6
Expected return on assets (a)	(22.6		)	(22.9		)	(23.6		)
Amortization of unrecognized:
Actuarial gain	9.8			6.4			9.3
Prior service cost	3.3			2.8			2.8
Net periodic benefit cost	$	14.9		$	9.7		$	11.3

Net Periodic Benefit Cost - Postretirement
	Years ended December 31,
$ in millions	2015			2014			2013
Service cost	$	0.2		$	0.2		$	0.2
Interest cost	0.6			0.8			0.8
Expected return on assets (a)	(0.1		)	(0.2		)	(0.2		)
Amortization of unrecognized:
Actuarial loss	(0.6		)	(0.8		)	(0.7		)
Prior service cost	0.1			0.1			0.1
Net periodic benefit cost	$	0.2		$	0.1		$	0.2

Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income, Regulatory Assets And Regulatory Liabilities

Estimated amounts that will be amortized from AOCI, Regulatory assets and Regulatory liabilities into net periodic benefit costs during 2016 are:

$ in millions	Pension		Postretirement
Actuarial gain / (loss)	$	7.2	$	(0.8	)
Prior service cost	$	3.1	$	0.1

Weighted Average Assumptions Used to Determine Benefit Obligations

The weighted average assumptions used to determine benefit obligations during the years ended December 31, 2015, 2014 and 2013 were:

Benefit Obligation Assumptions	Pension			Postretirement
	2015	2014	2013	2015	2014	2013
Discount rate for obligations	4.49%	4.02%	4.86%	4.10%	3.71%	4.58%
Rate of compensation increases	3.94%	3.94%	3.94%	N/A	N/A	N/A

Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost (Income)

The weighted-average assumptions used to determine net periodic benefit cost (income) for the years ended December 31, 2015, 2014 and 2013 were:

Net Periodic Benefit Cost / (Income) Assumptions	Pension			Postretirement
	2015	2014	2013	2015	2014	2013
Discount rate	4.02%	4.86%	4.04%	3.81%	4.51%	4.58%
Expected rate of return on plan assets	6.50%	6.75%	6.75%	4.50%	6.00%	6.00%
Rate of compensation increases	3.94%	3.94%	3.94%	N/A	N/A	N/A

Assumed Health Care Cost Trend Rates

The assumed health care cost trend rates at December 31, 2015, 2014 and 2013 are as follows:

Health Care Cost Assumptions	Expense			Benefit Obligation
	2015	2014	2013	2015	2014	2013
Pre - age 65
Current health care cost trend rate	6.97%	7.75%	8.00%	6.85%	6.97%	7.75%
Year trend reaches ultimate	2029	2023	2019	2036	2029	2023
Post - age 65
Current health care cost trend rate	6.97%	6.75%	7.50%	6.85%	6.97%	6.75%
Year trend reaches ultimate	2029	2021	2018	2036	2029	2021
Ultimate health care cost trend rate	4.50%	5.00%	5.00%	4.50%	4.50%	5.00%

Effect of Change in Health Care Cost Trend Rate

Effect of change in health care cost trend rate
$ in millions	One-percent increase		One-percent decrease
Service cost plus interest cost	$	0.1	$	—
Benefit obligation	$	1.1	$	(0.7	)

Schedule of Allocation of Plan Assets

The following table summarizes our target pension plan allocation for 2015:

		Percentage of plan assets as of December 31,
Asset Category	Long-Term Mid-Point Target Allocation	2015	2014
Equity Securities	28%	17%	18%
Debt Securities	72%	67%	69%
Real Estate	—%	9%	7%
Other	—%	7%	6%

Fair Value Measurements for Plan Assets

The fair values of our pension plan assets at December 31, 2015 by asset category are as follows:

Fair Value Measurements for Pension Plan Assets at December 31, 2015
Asset Category $ in millions	Market Value at December 31, 2015		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
Equity securities(a)
Small/Mid cap equity	$	9.2	$	9.2	$	—	$	—
Large cap equity	20.2		20.2		—		—
International equity	18.2		18.2		—		—
Emerging markets equity	2.7		2.7		—		—
SIIT dynamic equity	10.0		10.0		—		—
Total equity securities	60.3		60.3		—		—
Debt Securities(b)
Emerging markets debt	6.3		6.3		—		—
High yield bond	6.3		6.3		—		—
Long duration fund	219.5		219.5		—		—
Total debt securities	232.1		232.1		—		—
Other investments(c)
Core property collective fund	30.2		—		30.2		—
Common collective fund	22.8		—		22.8		—
Total other investments	53.0		—		53.0		—
Total pension plan assets	$	345.4	$	292.4	$	53.0	$	—

(a) This category includes investments in equity securities of large, small and medium sized companies and equity securities of foreign companies including those in developing countries. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(b) This category includes investments in investment-grade fixed-income instruments, U.S. dollar-denominated debt securities of emerging market issuers and high yield fixed-income securities that are rated below investment grade. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(c) This category represents a property fund that invests in commercial real estate and a hedge fund of funds made up of 30+ different hedge fund managers diversified over eight different hedge strategies. The fair value of the hedge fund is valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

The fair values of our pension plan assets at December 31, 2014 by asset category are as follows:

Fair Value Measurements for Pension Plan Assets at December 31, 2014
Asset Category $ in millions	Market Value at December 31, 2014		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
Equity securities(a)
Small/Mid cap equity	$	10.6	$	10.6	$	—	$	—
Large cap equity	22.2		22.2		—		—
International equity	18.2		18.2		—		—
Emerging markets equity	2.8		2.8		—		—
SIIT dynamic equity	11.6		11.6		—		—
Total equity securities	65.4		65.4		—		—
Debt Securities(b)
Emerging markets debt	6.0		6.0		—		—
High yield bond	6.5		6.5		—		—
Long duration fund	242.7		242.7		—		—
Total debt securities	255.2		255.2		—		—
Cash and cash equivalents(c)
Cash	1.6		1.6		—		—
Other investments(d)
Core property collective fund	26.3		—		26.3		—
Common collective fund	23.2		—		23.2		—
Total other investments	49.5		—		49.5		—
Total pension plan assets	$	371.7	$	322.2	$	49.5	$	—

(a) This category includes investments in equity securities of large, small and medium sized companies and equity securities of foreign companies including those in developing countries. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(b) This category includes investments in investment-grade fixed-income instruments, U.S. dollar-denominated debt securities of emerging market issuers and high yield fixed-income securities that are rated below investment grade. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(c) This category comprises cash held to pay beneficiaries. The fair value of cash equals its book value.

(d) This category represents a property fund that invests in commercial real estate and a hedge fund of funds made up of 30+ different hedge fund managers diversified over eight different hedge strategies. The fair value of the hedge fund is valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

Estimated Future Benefit Payments and Medicare Part D Reimbursements

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

Estimated future benefit payments and Medicare Part D reimbursements
$ in millions due within the following years:	Pension		Postretirement
2016	$	24.6	$	1.7
2017	$	25.2	$	1.6
2018	$	25.8	$	1.5
2019	$	26.3	$	1.4
2020	$	26.7	$	1.4
2021 - 2025	$	134.8	$	5.7

Pension [Member]

Fair Value Measurements for Plan Assets

The fair values of our pension plan assets at December 31, 2015 by asset category are as follows:

Fair Value Measurements for Pension Plan Assets at December 31, 2015
Asset Category $ in millions	Market Value at December 31, 2015		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
Equity securities(a)
Small/Mid cap equity	$	9.2	$	9.2	$	—	$	—
Large cap equity	20.2		20.2		—		—
International equity	18.2		18.2		—		—
Emerging markets equity	2.7		2.7		—		—
SIIT dynamic equity	10.0		10.0		—		—
Total equity securities	60.3		60.3		—		—
Debt securities(b)
Emerging markets debt	6.3		6.3		—		—
High yield bond	6.3		6.3		—		—
Long duration fund	219.5		219.5		—		—
Total debt securities	232.1		232.1		—		—
Other investments(c)
Core property collective fund	30.2		—		30.2		—
Common collective fund	22.8		—		22.8		—
Total other investments	53.0		—		53.0		—
Total pension plan assets	$	345.4	$	292.4	$	53.0	$	—

(a) This category includes investments in equity securities of large, small and medium sized companies and equity securities of foreign companies including those in developing countries. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(b) This category includes investments in investment-grade fixed-income instruments, U.S. dollar-denominated debt securities of emerging market issuers and high yield fixed-income securities that are rated below investment grade. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(c) This category represents a property fund that invests in commercial real estate and a hedge fund of funds made up of 30+ different hedge fund managers diversified over eight different hedge strategies. The fair value of the hedge fund is valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

The fair values of our pension plan assets at December 31, 2014 by asset category are as follows:

Fair Value Measurements for Pension Plan Assets at December 31, 2014
Asset Category $ in millions	Market Value at December 31, 2014		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
Equity securities(a)
Small/Mid cap equity	$	10.6	$	10.6	$	—	$	—
Large cap equity	22.2		22.2		—		—
International equity	18.2		18.2		—		—
Emerging markets equity	2.8		2.8		—		—
SIIT dynamic equity	11.6		11.6		—		—
Total equity securities	65.4		65.4		—		—
Debt securities(b)
Emerging markets debt	6.0		6.0		—		—
High yield bond	6.5		6.5		—		—
Long duration fund	242.7		242.7		—		—
Total debt securities	255.2		255.2		—		—
Cash and cash equivalents(c)
Cash	1.6		1.6		—		—
Other investments(d)
Core property collective fund	26.3		—		26.3		—
Common collective fund	23.2		—		23.2		—
Total other investments	49.5		—		49.5		—
Total pension plan assets	$	371.7	$	322.2	$	49.5	$	—

(a) This category includes investments in equity securities of large, small and medium sized companies and equity securities of foreign companies including those in developing countries. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(b) This category includes investments in investment-grade fixed-income instruments, U.S. dollar-denominated debt securities of emerging market issuers and high yield fixed-income securities that are rated below investment grade. The funds are valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

(c) This category comprises cash held to pay beneficiaries. The fair value of cash equals its book value.

(d) This category represents a property fund that invests in commercial real estate and a hedge fund of funds made up of 30+ different hedge fund managers diversified over eight different hedge strategies. The fair value of the hedge fund is valued using the net asset value method in which an average of the market prices for the underlying investments is used to value the fund.

Pension [Member] | THE DAYTON POWER AND LIGHT COMPANY [Member]

Pension And Postretirement Benefit Plans' Obligations And Assets

$ in millions	Pension
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at beginning of period	$	443.8		$	370.5
Service cost	7.1			5.9
Interest cost	17.3			17.5
Plan amendments	—			6.8
Actuarial (gain) / loss	(34.5		)	67.3
Benefits paid	(22.9		)	(24.2		)
Benefit obligation at end of period	410.8			443.8
Change in plan assets
Fair value of plan assets at beginning of period	371.7			349.1
Actual return on plan assets	(8.8		)	46.4
Contributions to plan assets	5.4			0.4
Benefits paid	(22.9		)	(24.2		)
Fair value of plan assets at end of period	345.4			371.7
Funded status of plan	$	(65.4	)	$	(72.1	)
	December 31,
	2015			2014
Amounts recognized in the Balance sheets
Current liabilities	$	(0.4	)	$	(0.4	)
Non-current liabilities	(65.0		)	(71.7		)
Net liability at Year ended December 31,	$	(65.4	)	$	(72.1	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	17.0		$	20.3
Net actuarial loss / (gain)	139.7			152.5
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	156.7		$	172.8
Recorded as:
Regulatory asset	$	91.1		$	99.0
Regulatory liability	—			—
Accumulated other comprehensive income	65.6			73.8
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	156.7		$	172.8

Other Changes in Plan Assets and Benefit Obligation Recognized in Accumulated Other Comprehensive Income, Regulatory Assets And Regulatory Liabilities

Pension
	Years ended December 31,
$ in millions	2015			2014			2013
Net actuarial loss / (gain)	$	(3.0	)	$	43.8		$	(11.7	)
Prior service cost	—			6.8			—
Reversal of amortization item:
Net actuarial loss	(9.8		)	(6.4		)	(9.3		)
Prior service cost	(3.3		)	(2.8		)	(2.8		)
Total recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(16.1	)	$	41.4		$	(23.8	)
Total recognized in net periodic benefit cost and Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(1.2	)	$	51.1		$	(12.5	)

Postretirement
	Years ended December 31,
$ in millions	2015			2014			2013
Net actuarial loss / (gain)	$	(1.1	)	$	0.4		$	(1.9	)
Reversal of amortization item:
Net actuarial gain	0.6			0.8			0.7
Prior service credit	(0.1		)	(0.1		)	(0.1		)
Total recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(0.6	)	$	1.1		$	(1.3	)
Total recognized in net periodic benefit cost and Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities	$	(0.4	)	$	1.2		$	(1.1	)

Postretirement [Member]

Fair Value Measurements for Plan Assets

The fair values of our other postemployment benefit plan assets at December 31, 2015 by asset category are as follows:

Fair Value Measurements for Other Postemployment Benefit Plan Assets at December 31, 2015
Asset Category $ in millions	Market Value at December 31, 2015		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
JP Morgan Core Bond Fund (a)	$	2.8	$	2.8	$	—	$	—

(a) This category includes investments in U.S. government obligations and mortgage-backed and asset-backed securities.

The fair values of our other postemployment benefit plan assets at December 31, 2014 by asset category are as follows:

Fair Value Measurements for Other Postemployment Benefit Plan Assets at December 31, 2014
Asset Category $ in millions	Market Value at December 31, 2014		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
JP Morgan Core Bond Fund (a)	$	3.3	$	3.3	$	—	$	—

(a) This category includes investments in U.S. government obligations and mortgage-backed and asset-backed securities.

Postretirement [Member] | THE DAYTON POWER AND LIGHT COMPANY [Member]

Pension And Postretirement Benefit Plans' Obligations And Assets

$ in millions	Postretirement
	Years ended December 31,
	2015			2014
Change in benefit obligation
Benefit obligation at beginning of period	$	19.6		$	19.7
Service cost	0.2			0.2
Interest cost	0.6			0.8
Actuarial (gain) / loss	(1.1		)	0.2
Benefits paid	(1.5		)	(1.3		)
Benefit obligation at end of period	17.8			19.6
Change in plan assets
Fair value of plan assets at beginning of period	3.3			3.7
Contributions to plan assets	1.0			0.9
Benefits paid	(1.5		)	(1.3		)
Fair value of plan assets at end of period	2.8			3.3
Funded status of plan	$	(15.0	)	$	(16.3	)
	December 31,
	2015			2014
Amounts recognized in the Balance sheets
Current liabilities	$	(0.4	)	$	(0.5	)
Non-current liabilities	(14.6		)	(15.8		)
Net liability at Year ended December 31,	$	(15.0	)	$	(16.3	)
Amounts recognized in Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax
Components:
Prior service cost	$	0.5		$	0.6
Net actuarial loss / (gain)	(6.2		)	(5.8		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.7	)	$	(5.2	)
Recorded as:
Regulatory asset	$	0.3		$	—
Regulatory liability	(5.1		)	(4.5		)
Accumulated other comprehensive income	(0.9		)	(0.7		)
Accumulated Other Comprehensive Income, Regulatory Assets and Regulatory Liabilities, pre-tax	$	(5.7	)	$	(5.2	)

Fair Value Measurements for Plan Assets

The fair values of our other postemployment benefit plan assets at December 31, 2015 by asset category are as follows:

Fair Value Measurements for Other Postemployment Benefit Plan Assets at December 31, 2015
Asset Category $ in millions	Fair Value at December 31, 2015 (a)		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
JP Morgan Core Bond Fund (a)	$	2.8	$	2.8	$	—	$	—

(a) This category includes investments in U.S. government obligations and mortgage-backed and asset-backed securities.

The fair values of our other postemployment benefit plan assets at December 31, 2014 by asset category are as follows:

Fair Value Measurements for Other Postemployment Benefit Plan Assets at December 31, 2014
Asset Category $ in millions	Fair Value at December 31, 2014 (a)		Quoted prices in active markets for identical assets		Significant observable inputs		Significant unobservable inputs
			(Level 1)		(Level 2)		(Level 3)
JP Morgan Core Bond Fund (a)	$	3.2	$	3.2	$	—	$	—

(a) This category includes investments in U.S. government obligations and mortgage-backed and asset-backed securities.