Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2015

Components of Net Periodic Benefit Cost

	Pension Plans						Other Postretirement Benefit Plans
	Three Months Ended June 30,						Three Months Ended June 30,
	2015			2014			2015			2014
	(in millions)
Service Cost	$	24		$	18		$	3		$	3
Interest Cost	52			56			14			17
Expected Return on Plan Assets	(68		)	(65		)	(27		)	(28		)
Amortization of Prior Service Credit	—			—			(17		)	(17		)
Amortization of Net Actuarial Loss	26			31			4			6
Net Periodic Benefit Cost (Credit)	$	34		$	40		$	(23	)	$	(19	)

	Pension Plans						Other Postretirement Benefit Plans
	Six Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
	(in millions)
Service Cost	$	47		$	36		$	6		$	7
Interest Cost	103			111			28			34
Expected Return on Plan Assets	(137		)	(131		)	(55		)	(56		)
Amortization of Prior Service Cost (Credit)	1			1			(34		)	(34		)
Amortization of Net Actuarial Loss	53			62			9			11
Net Periodic Benefit Cost (Credit)	$	67		$	79		$	(46	)	$	(38	)

Appalachian Power Co [Member]

Components of Net Periodic Benefit Cost

APCo

	Pension Plans						Other Postretirement Benefit Plans
	Three Months Ended June 30,						Three Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	2,175		$	1,759		$	285		$	362
Interest Cost	6,679			7,406			2,585			3,197
Expected Return on Plan Assets	(8,746		)	(8,481		)	(4,529		)	(4,633		)
Amortization of Prior Service Cost (Credit)	45			49			(2,512		)	(2,512		)
Amortization of Net Actuarial Loss	3,474			4,148			899			1,145
Net Periodic Benefit Cost (Credit)	$	3,627		$	4,881		$	(3,272	)	$	(2,441	)

	Pension Plans						Other Postretirement Benefit Plans
	Six Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	4,350		$	3,518		$	571		$	724
Interest Cost	13,358			14,812			5,169			6,394
Expected Return on Plan Assets	(17,491		)	(16,963		)	(9,058		)	(9,266		)
Amortization of Prior Service Cost (Credit)	90			99			(5,025		)	(5,025		)
Amortization of Net Actuarial Loss	6,947			8,296			1,799			2,291
Net Periodic Benefit Cost (Credit)	$	7,254		$	9,762		$	(6,544	)	$	(4,882	)

Indiana Michigan Power Co [Member]

Components of Net Periodic Benefit Cost

I&M

	Pension Plans						Other Postretirement Benefit Plans
	Three Months Ended June 30,						Three Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	3,217		$	2,517		$	407		$	487
Interest Cost	6,115			6,574			1,592			1,910
Expected Return on Plan Assets	(8,116		)	(7,748		)	(3,304		)	(3,363		)
Amortization of Prior Service Cost (Credit)	46			48			(2,356		)	(2,356		)
Amortization of Net Actuarial Loss	3,144			3,646			507			592
Net Periodic Benefit Cost (Credit)	$	4,406		$	5,037		$	(3,154	)	$	(2,730	)

	Pension Plans						Other Postretirement Benefit Plans
	Six Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	6,434		$	5,034		$	813		$	974
Interest Cost	12,230			13,147			3,184			3,819
Expected Return on Plan Assets	(16,232		)	(15,496		)	(6,608		)	(6,727		)
Amortization of Prior Service Cost (Credit)	91			97			(4,711		)	(4,711		)
Amortization of Net Actuarial Loss	6,289			7,292			1,013			1,184
Net Periodic Benefit Cost (Credit)	$	8,812		$	10,074		$	(6,309	)	$	(5,461	)

Ohio Power Co [Member]

Components of Net Periodic Benefit Cost

OPCo

	Pension Plans						Other Postretirement Benefit Plans
	Three Months Ended June 30,						Three Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	1,672		$	1,285		$	215		$	257
Interest Cost	5,070			5,526			1,615			1,900
Expected Return on Plan Assets	(6,878		)	(6,606		)	(3,378		)	(3,380		)
Amortization of Prior Service Cost (Credit)	35			39			(1,730		)	(1,730		)
Amortization of Net Actuarial Loss	2,644			3,105			518			595
Net Periodic Benefit Cost (Credit)	$	2,543		$	3,349		$	(2,760	)	$	(2,358	)

	Pension Plans						Other Postretirement Benefit Plans
	Six Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	3,344		$	2,570		$	431		$	513
Interest Cost	10,140			11,052			3,230			3,801
Expected Return on Plan Assets	(13,756		)	(13,213		)	(6,754		)	(6,760		)
Amortization of Prior Service Cost (Credit)	70			78			(3,461		)	(3,461		)
Amortization of Net Actuarial Loss	5,288			6,211			1,035			1,190
Net Periodic Benefit Cost (Credit)	$	5,086		$	6,698		$	(5,519	)	$	(4,717	)

Public Service Co Of Oklahoma [Member]

Components of Net Periodic Benefit Cost

PSO

	Pension Plans						Other Postretirement Benefit Plans
	Three Months Ended June 30,						Three Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	1,599		$	1,302		$	169		$	210
Interest Cost	2,732			3,014			759			894
Expected Return on Plan Assets	(3,786		)	(3,651		)	(1,577		)	(1,575		)
Amortization of Prior Service Cost (Credit)	63			74			(1,072		)	(1,073		)
Amortization of Net Actuarial Loss	1,417			1,688			241			277
Net Periodic Benefit Cost (Credit)	$	2,025		$	2,427		$	(1,480	)	$	(1,267	)

	Pension Plans						Other Postretirement Benefit Plans
	Six Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	3,198		$	2,604		$	339		$	420
Interest Cost	5,463			6,028			1,518			1,787
Expected Return on Plan Assets	(7,572		)	(7,302		)	(3,154		)	(3,150		)
Amortization of Prior Service Cost (Credit)	126			148			(2,145		)	(2,145		)
Amortization of Net Actuarial Loss	2,834			3,376			483			554
Net Periodic Benefit Cost (Credit)	$	4,049		$	4,854		$	(2,959	)	$	(2,534	)

Southwestern Electric Power Co [Member]

Components of Net Periodic Benefit Cost

SWEPCo

	Pension Plans						Other Postretirement Benefit Plans
	Three Months Ended June 30,						Three Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	2,082		$	1,654		$	210		$	253
Interest Cost	2,932			3,162			838			998
Expected Return on Plan Assets	(4,008		)	(3,857		)	(1,736		)	(1,754		)
Amortization of Prior Service Cost (Credit)	77			88			(1,289		)	(1,289		)
Amortization of Net Actuarial Loss	1,507			1,762			266			308
Net Periodic Benefit Cost (Credit)	$	2,590		$	2,809		$	(1,711	)	$	(1,484	)

	Pension Plans						Other Postretirement Benefit Plans
	Six Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
	(in thousands)
Service Cost	$	4,163		$	3,309		$	421		$	506
Interest Cost	5,864			6,325			1,675			1,996
Expected Return on Plan Assets	(8,016		)	(7,714		)	(3,471		)	(3,508		)
Amortization of Prior Service Cost (Credit)	154			175			(2,578		)	(2,578		)
Amortization of Net Actuarial Loss	3,014			3,523			532			617
Net Periodic Benefit Cost (Credit)	$	5,179		$	5,618		$	(3,421	)	$	(2,967	)