Business Segments (Tables)

9 Months Ended

Sep. 30, 2017

Segment Reporting Information [Line Items]

Reportable Segment Information

	Three Months Ended September 30, 2017
	Vertically Integrated Utilities		Transmission and Distribution Utilities		AEP Transmission Holdco		Generation & Marketing			Corporate and Other (a)		Reconciling Adjustments			Consolidated
	(in millions)
Revenues from:
External Customers	$	2,453.8	$	1,149.7	$	45.1	$	441.5		$	14.6	$	—		$	4,104.7
Other Operating Segments	28.4		23.6		133.4		24.0			16.7		(226.1		)	—
Total Revenues	$	2,482.2	$	1,173.3	$	178.5	$	465.5		$	31.3	$	(226.1	)	$	4,104.7
Income (Loss) from Continuing Operations	$	297.3	$	144.0	$	76.5	$	33.7		$	5.2	$	—		$	556.7
Loss from Discontinued Operations, Net of Tax	—		—		—		—			—		—			—
Net Income (Loss)	$	297.3	$	144.0	$	76.5	$	33.7		$	5.2	$	—		$	556.7
	Three Months Ended September 30, 2016
	Vertically Integrated Utilities		Transmission and Distribution Utilities		AEP Transmission Holdco		Generation & Marketing			Corporate and Other (a)		Reconciling Adjustments			Consolidated
	(in millions)
Revenues from:
External Customers	$	2,538.3	$	1,245.4	$	39.5	$	823.3		$	5.7	$	—		$	4,652.2
Other Operating Segments	18.0		30.2		92.9		36.1			19.1		(196.3		)	—
Total Revenues	$	2,556.3	$	1,275.6	$	132.4	$	859.4		$	24.8	$	(196.3	)	$	4,652.2
Income (Loss) from Continuing Operations	$	343.4	$	155.7	$	69.5	$	(1,369.2	)	$	36.4	$	—		$	(764.2	)
Loss from Discontinued Operations, Net of Tax	—		—		—		—			—		—			—
Net Income (Loss)	$	343.4	$	155.7	$	69.5	$	(1,369.2	)	$	36.4	$	—		$	(764.2	)

	Nine Months Ended September 30, 2017
	Vertically Integrated Utilities		Transmission and Distribution Utilities		AEP Transmission Holdco		Generation & Marketing			Corporate and Other (a)			Reconciling Adjustments			Consolidated
	(in millions)
Revenues from:
External Customers	$	6,819.3	$	3,242.7	$	125.8	$	1,386.8		$	39.9		$	—		$	11,614.5
Other Operating Segments	73.8		70.5		456.1		80.7			46.8			(727.9		)	—
Total Revenues	$	6,893.1	$	3,313.2	$	581.9	$	1,467.5		$	86.7		$	(727.9	)	$	11,614.5
Income (Loss) from Continuing Operations	$	639.2	$	374.3	$	278.3	$	246.3		$	(11.0	)	$	—		$	1,527.1
Loss from Discontinued Operations, Net of Tax	—		—		—		—			—			—			—
Net Income (Loss)	$	639.2	$	374.3	$	278.3	$	246.3		$	(11.0	)	$	—		$	1,527.1
	Nine Months Ended September 30, 2016
	Vertically Integrated Utilities		Transmission and Distribution Utilities		AEP Transmission Holdco		Generation & Marketing			Corporate and Other (a)			Reconciling Adjustments			Consolidated
	(in millions)
Revenues from:
External Customers	$	6,864.6	$	3,398.9	$	110.1	$	2,192.5		$	23.9		$	—		$	12,590.0
Other Operating Segments	63.2		69.6		272.6		98.7			55.2			(559.3		)	—
Total Revenues	$	6,927.8	$	3,468.5	$	382.7	$	2,291.2		$	79.1		$	(559.3	)	$	12,590.0
Income (Loss) from Continuing Operations	$	832.6	$	387.8	$	209.5	$	(1,248.8	)	$	64.2		$	—		$	245.3
Loss from Discontinued Operations, Net of Tax	—		—		—		—			(2.5		)	—			(2.5		)
Net Income (Loss)	$	832.6	$	387.8	$	209.5	$	(1,248.8	)	$	61.7		$	—		$	242.8

	September 30, 2017
	Vertically Integrated Utilities		Transmission and Distribution Utilities		AEP Transmission Holdco		Generation & Marketing			Corporate and Other (a)		Reconciling Adjustments				Consolidated
	(in millions)
Total Property, Plant and Equipment	$	42,722.9	$	15,695.2	$	6,394.2	$	632.9		$	359.5	$	(366.5	)	(b)	$	65,438.2
Accumulated Depreciation and Amortization	13,042.9		3,766.2		156.6		161.7			180.8		(186.5		)	(b)	17,121.7
Total Property Plant and Equipment - Net	$	29,680.0	$	11,929.0	$	6,237.6	$	471.2		$	178.7	$	(180.0	)	(b)	$	48,316.5
Total Assets	$	38,136.4	$	15,765.0	$	7,631.2	$	1,904.4		$	22,339.9	$	(21,812.0	)	(b) (c)	$	63,964.9
Long-term Debt Due Within One Year:
Non-Affiliated	$	1,107.2	$	703.4	$	—	$	0.1		$	548.6	$	—			$	2,359.3
Long-term Debt:
Affiliated	50.0		—		—		32.2			—		(82.2		)		—
Non-Affiliated	10,644.2		4,738.0		2,682.1		(0.3		)	298.4		—				18,362.4
Total Long-term Debt	$	11,801.4	$	5,441.4	$	2,682.1	$	32.0		$	847.0	$	(82.2	)		$	20,721.7
	December 31, 2016
	Vertically Integrated Utilities		Transmission and Distribution Utilities		AEP Transmission Holdco		Generation & Marketing			Corporate and Other (a)		Reconciling Adjustments				Consolidated
	(in millions)
Total Property, Plant and Equipment	$	41,552.6	$	14,762.2	$	5,354.0	$	364.7		$	356.6	$	(353.5	)	(b)	$	62,036.6
Accumulated Depreciation and Amortization	12,596.7		3,655.0		101.4		42.2			186.0		(184.0		)	(b)	16,397.3
Total Property Plant and Equipment - Net	$	28,955.9	$	11,107.2	$	5,252.6	$	322.5		$	170.6	$	(169.5	)	(b)	$	45,639.3
Assets Held for Sale	$	—	$	—	$	—	$	1,951.2		$	—	$	—			$	1,951.2
Total Assets	$	37,428.3	$	14,802.4	$	6,384.8	$	3,386.1		$	20,354.8	$	(18,888.7	)	(b) (c)	$	63,467.7
Long-term Debt Due Within One Year:
Non-Affiliated	$	1,519.9	$	309.4	$	—	$	500.1		$	548.6	$	—			$	2,878.0
Long-term Debt:
Affiliated	20.0		—		—		32.2			—		(52.2		)		—
Non-Affiliated	10,353.3		4,672.2		2,055.7		—			297.2		—				17,378.4
Total Long-term Debt	$	11,893.2	$	4,981.6	$	2,055.7	$	532.3		$	845.8	$	(52.2	)		$	20,256.4
Liabilities Held for Sale	$	—	$	—	$	—	$	235.9		$	—	$	—			$	235.9

(a) Corporate and Other primarily includes the purchasing of receivables from certain AEP utility subsidiaries, Parent’s guarantee revenue received from affiliates, investment income, interest income and interest expense and other nonallocated costs.

(b) Includes eliminations due to an intercompany capital lease.

(c) Reconciling Adjustments for Total Assets primarily include the elimination of intercompany advances to affiliates and intercompany accounts receivable along with the elimination of AEP’s investments in subsidiary companies.

AEP Transmission Co [Member]

Segment Reporting Information [Line Items]

Reportable Segment Information

	Three Months Ended September 30, 2017
	State Transcos		AEPTCo Parent		Reconciling Adjustments				AEPTCo Consolidated
	(in millions)
Revenues from:
External Customers	$	35.9	$	—	$	—			$	35.9
Sales to AEP Affiliates	131.3		—		0.1				131.4
Total Revenues	$	167.2	$	—	$	0.1			$	167.3
Interest Income	$	—	$	19.5	$	(19.3	)	(a)	$	0.2
Interest Expense	16.9		19.3		(19.3		)	(a)	16.9
Income Tax Expense	30.2		—		—				30.2
Equity Earnings in State Transcos	—		59.8		(59.8		)	(b)	—
Net Income	$	59.8	$	59.9	$	(59.8	)	(b)	$	59.9

	Three Months Ended September 30, 2016
	State Transcos		AEPTCo Parent		Reconciling Adjustments				AEPTCo Consolidated
	(in millions)
Revenues from:
External Customers	$	33.5	$	—	$	—			$	33.5
Sales to AEP Affiliates	91.8		—		—				91.8
Total Revenues	$	125.3	$	—	$	—			$	125.3
Interest Income	$	—	$	14.0	$	(13.9	)	(a)	$	0.1
Interest Expense	11.0		13.9		(13.9		)	(a)	11.0
Income Tax Expense	26.4		—		—				26.4
Equity Earnings in State Transcos	—		52.3		(52.3		)	(b)	—
Net Income	$	52.3	$	52.4	$	(52.3	)	(b)	$	52.4

	Nine Months Ended September 30, 2017
	State Transcos		AEPTCo Parent		Reconciling Adjustments				AEPTCo Consolidated
	(in millions)
Revenues from:
External Customers	$	99.2	$	—	$	—			$	99.2
Sales to AEP Affiliates	450.2		—		—				450.2
Total Revenues	$	549.4	$	—	$	—			$	549.4
Interest Income	$	0.1	$	58.0	$	(57.6	)	(a)	$	0.5
Interest Expense	48.6		57.6		(57.6		)	(a)	48.6
Income Tax Expense	114.3		0.2		—				114.5
Equity Earnings in State Transcos	—		224.0		(224.0		)	(b)	—
Net Income	$	224.0	$	224.3	$	(224.0	)	(b)	$	224.3

	Nine Months Ended September 30, 2016
	State Transcos		AEPTCo Parent		Reconciling Adjustments				AEPTCo Consolidated
	(in millions)
Revenues from:
External Customers	$	89.6	$	—	$	—			$	89.6
Sales to AEP Affiliates	268.4		—		—				268.4
Total Revenues	$	358.0	$	—	$	—			$	358.0
Interest Income	$	—	$	41.8	$	(41.6	)	(a)	$	0.2
Interest Expense	32.3		41.6		(41.6		)	(a)	32.3
Income Tax Expense	73.9		—		—				73.9
Equity Earnings in State Transcos	—		153.0		(153.0		)	(b)	—
Net Income	$	153.0	$	153.0	$	(153.0	)	(b)	$	153.0

	September 30, 2017
	State Transcos		AEPTCo Parent		Reconciling Adjustments				AEPTCo Consolidated
	(in millions)
Total Transmission Property	$	6,067.5	$	—	$	—			$	6,067.5
Accumulated Depreciation and Amortization	151.5		—		—				151.5
Total Transmission Property – Net	$	5,916.0	$	—	$	—			$	5,916.0
Notes Receivable - Affiliated	$	—	$	2,500.0	$	(2,500.0	)	(c)	$	—
Total Assets	$	6,455.2	$	5,010.8	$	(4,917.1	)	(d)	$	6,548.9
Total Long-term Debt	$	2,475.6	$	2,574.4	$	(2,500.0	)	(c)	$	2,550.0

	December 31, 2016
	State Transcos		AEPTCo Parent		Reconciling Adjustments				AEPTCo Consolidated
	(in millions)
Total Transmission Property	$	5,054.2	$	—	$	—			$	5,054.2
Accumulated Depreciation and Amortization	99.6		—		—				99.6
Total Transmission Property – Net	$	4,954.6	$	—	$	—			$	4,954.6
Notes Receivable - Affiliated	$	—	$	1,950.0	$	(1,950.0	)	(c)	$	—
Total Assets	$	5,337.5	$	3,947.8	$	(3,935.5	)	(d)	$	5,349.8
Total Long-term Debt	$	1,932.0	$	1,950.0	$	(1,950.0	)	(c)	$	1,932.0

(a) Elimination of intercompany interest income/interest expense on affiliated debt arrangement.

(b) Elimination of AEPTCo Parent’s equity earnings in the State Transcos.

(c) Elimination of intercompany debt.

(d) Primarily relates to the elimination of AEPTCo Parent’s investment in the State Transcos and Note Receivable from the State Transcos.