Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2018

Components of Net Periodic Benefit Cost

AEP

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	24.4		$	24.1		$	2.9		$	2.8
Interest Cost	47.0			50.8			11.9			14.9
Expected Return on Plan Assets	(72.6		)	(71.2		)	(25.6		)	(25.4		)
Amortization of Prior Service Cost (Credit)	—			0.2			(17.2		)	(17.2		)
Amortization of Net Actuarial Loss	21.3			20.7			2.6			9.1
Net Periodic Benefit Cost (Credit)	$	20.1		$	24.6		$	(25.4	)	$	(15.8	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	48.8		$	48.2		$	5.8		$	5.6
Interest Cost	93.9			101.6			23.7			29.7
Expected Return on Plan Assets	(145.1		)	(142.4		)	(51.1		)	(50.7		)
Amortization of Prior Service Cost (Credit)	—			0.5			(34.5		)	(34.5		)
Amortization of Net Actuarial Loss	42.6			41.4			5.2			18.3
Net Periodic Benefit Cost (Credit)	$	40.2		$	49.3		$	(50.9	)	$	(31.6	)

AEP Texas

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	2.3		$	2.2		$	0.1		$	0.2
Interest Cost	4.0			4.3			1.0			1.3
Expected Return on Plan Assets	(6.4		)	(6.3		)	(2.2		)	(2.2		)
Amortization of Prior Service Credit	—			—			(1.4		)	(1.5		)
Amortization of Net Actuarial Loss	1.8			1.7			0.2			0.8
Net Periodic Benefit Cost (Credit)	$	1.7		$	1.9		$	(2.3	)	$	(1.4	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	4.6		$	4.3		$	0.4		$	0.4
Interest Cost	8.0			8.6			1.9			2.5
Expected Return on Plan Assets	(12.8		)	(12.6		)	(4.3		)	(4.4		)
Amortization of Prior Service Credit	—			—			(2.9		)	(2.9		)
Amortization of Net Actuarial Loss	3.6			3.5			0.4			1.6
Net Periodic Benefit Cost (Credit)	$	3.4		$	3.8		$	(4.5	)	$	(2.8	)

APCo

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	2.3		$	2.4		$	0.2		$	0.2
Interest Cost	5.9			6.4			2.1			2.7
Expected Return on Plan Assets	(9.2		)	(9.0		)	(4.0		)	(4.1		)
Amortization of Prior Service Credit	—			—			(2.5		)	(2.5		)
Amortization of Net Actuarial Loss	2.7			2.6			0.5			1.5
Net Periodic Benefit Cost (Credit)	$	1.7		$	2.4		$	(3.7	)	$	(2.2	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	4.6		$	4.7		$	0.5		$	0.5
Interest Cost	11.8			12.8			4.1			5.3
Expected Return on Plan Assets	(18.3		)	(17.9		)	(8.0		)	(8.2		)
Amortization of Prior Service Cost (Credit)	—			0.1			(5.0		)	(5.0		)
Amortization of Net Actuarial Loss	5.3			5.2			1.0			3.1
Net Periodic Benefit Cost (Credit)	$	3.4		$	4.9		$	(7.4	)	$	(4.3	)

I&M

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	3.4		$	3.5		$	0.4		$	0.4
Interest Cost	5.5			6.0			1.3			1.8
Expected Return on Plan Assets	(8.9		)	(8.7		)	(3.1		)	(3.0		)
Amortization of Prior Service Cost (Credit)	—			0.1			(2.3		)	(2.4		)
Amortization of Net Actuarial Loss	2.4			2.5			0.3			1.1
Net Periodic Benefit Cost (Credit)	$	2.4		$	3.4		$	(3.4	)	$	(2.1	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	6.8		$	7.0		$	0.8		$	0.8
Interest Cost	11.0			12.1			2.7			3.5
Expected Return on Plan Assets	(17.8		)	(17.3		)	(6.2		)	(6.1		)
Amortization of Prior Service Cost (Credit)	—			0.1			(4.7		)	(4.7		)
Amortization of Net Actuarial Loss	4.9			4.9			0.6			2.2
Net Periodic Benefit Cost (Credit)	$	4.9		$	6.8		$	(6.8	)	$	(4.3	)

OPCo

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	1.8		$	1.9		$	0.3		$	0.2
Interest Cost	4.5			4.9			1.3			1.7
Expected Return on Plan Assets	(7.2		)	(7.0		)	(2.9		)	(3.0		)
Amortization of Prior Service Cost (Credit)	—			0.1			(1.8		)	(1.8		)
Amortization of Net Actuarial Loss	2.0			1.9			0.2			1.1
Net Periodic Benefit Cost (Credit)	$	1.1		$	1.8		$	(2.9	)	$	(1.8	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	3.8		$	3.8		$	0.5		$	0.4
Interest Cost	8.9			9.7			2.6			3.4
Expected Return on Plan Assets	(14.4		)	(14.0		)	(5.9		)	(6.0		)
Amortization of Prior Service Cost (Credit)	—			0.1			(3.5		)	(3.5		)
Amortization of Net Actuarial Loss	4.0			3.9			0.5			2.2
Net Periodic Benefit Cost (Credit)	$	2.3		$	3.5		$	(5.8	)	$	(3.5	)

PSO

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	1.8		$	1.6		$	0.2		$	0.1
Interest Cost	2.5			2.7			0.6			0.8
Expected Return on Plan Assets	(4.1		)	(4.0		)	(1.4		)	(1.4		)
Amortization of Prior Service Credit	—			—			(1.1		)	(1.0		)
Amortization of Net Actuarial Loss	1.1			1.1			0.2			0.5
Net Periodic Benefit Cost (Credit)	$	1.3		$	1.4		$	(1.5	)	$	(1.0	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	3.6		$	3.2		$	0.4		$	0.3
Interest Cost	4.9			5.4			1.2			1.6
Expected Return on Plan Assets	(8.1		)	(7.9		)	(2.8		)	(2.8		)
Amortization of Prior Service Credit	—			—			(2.1		)	(2.1		)
Amortization of Net Actuarial Loss	2.2			2.2			0.3			1.0
Net Periodic Benefit Cost (Credit)	$	2.6		$	2.9		$	(3.0	)	$	(2.0	)

SWEPCo

	Pension Plans						OPEB
	Three Months Ended June 30,						Three Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	2.3		$	2.2		$	0.2		$	0.2
Interest Cost	2.8			3.0			0.7			0.9
Expected Return on Plan Assets	(4.3		)	(4.2		)	(1.6		)	(1.6		)
Amortization of Prior Service Credit	—			—			(1.3		)	(1.3		)
Amortization of Net Actuarial Loss	1.2			1.2			0.2			0.6
Net Periodic Benefit Cost (Credit)	$	2.0		$	2.2		$	(1.8	)	$	(1.2	)

	Pension Plans						OPEB
	Six Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Service Cost	$	4.6		$	4.4		$	0.5		$	0.4
Interest Cost	5.7			6.1			1.4			1.8
Expected Return on Plan Assets	(8.7		)	(8.4		)	(3.2		)	(3.2		)
Amortization of Prior Service Credit	—			—			(2.6		)	(2.6		)
Amortization of Net Actuarial Loss	2.5			2.4			0.3			1.2
Net Periodic Benefit Cost (Credit)	$	4.1		$	4.5		$	(3.6	)	$	(2.4	)