AEP Texas 10-Q 26 Apr 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 25, 2019
Entity Registrant Name	AMERICAN ELECTRIC POWER CO INC
Entity Central Index Key	0000004904
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		493,435,530
AEP Texas Inc. [Member]
Entity Registrant Name	AEP Texas Inc.
Entity Central Index Key	0001721781
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		100
AEP Transmission Co [Member]
Entity Registrant Name	AEP Transmission Company, LLC
Entity Central Index Key	0001702494
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		0
Appalachian Power Co [Member]
Entity Registrant Name	APPALACHIAN POWER CO
Entity Central Index Key	0000006879
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		13,499,500
Indiana Michigan Power Co [Member]
Entity Registrant Name	INDIANA MICHIGAN POWER CO
Entity Central Index Key	0000050172
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		1,400,000
Ohio Power Co [Member]
Entity Registrant Name	OHIO POWER CO
Entity Central Index Key	0000073986
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		27,952,473
Public Service Co Of Oklahoma [Member]
Entity Registrant Name	PUBLIC SERVICE CO OF OKLAHOMA
Entity Central Index Key	0000081027
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		9,013,000
Southwestern Electric Power Co [Member]
Entity Registrant Name	SOUTHWESTERN ELECTRIC POWER CO
Entity Central Index Key	0000092487
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		7,536,640

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019		Mar. 31, 2018
Revenues
Revenue from Contracts with Customers	$ 4,056.8		$ 4,048.3
Sales to AEP Affiliates	0		0
TOTAL REVENUES	4,056.8		4,048.3
Expenses
Other Operation	666		726.4
Maintenance	274.5		298.5
Depreciation and Amortization	605.8		539.7
Taxes Other Than Income Taxes	309.9		285.6
TOTAL EXPENSES	3,268.4		3,342.3
OPERATING INCOME (LOSS)	788.4		706
Other Income (Expense):
Other Income	8.6		5.5
Allowance for Equity Funds Used During Construction	28.9		30.7
Non-Service Cost Components of Net Periodic Benefit Cost	30		32
Interest Expense	(255.8)		(234)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	600.1		540.2
Income Tax Expense (Benefit)	44.5		102
Equity Earnings (Loss) of Unconsolidated Subsidiaries	18.5		18.5
NET INCOME (LOSS)	574.1		456.7
Net Income Attributable to Noncontrolling Interests	1.3		2.3
EARNINGS ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 572.8		$ 454.4
Earnings Per Share
Weighted Average Number of Basic AEP Common Shares Outstanding	493,309,076		492,267,402
Total Basic Earnings Per Share Attributable to AEP Common Shareholders	$ 1.16		$ 0.92
Weighted Average Number of Diluted AEP Common Shares Outstanding	494,484,144		493,127,300
Total Diluted Earnings Per Share Attributable to AEP Common Shareholders	$ 1.16		$ 0.92
Common Stock, Dividends, Per Share, Declared	$ 0.67		$ 0.62
Vertically Integrated Utilities [Member]
Revenues
Revenue from Contracts with Customers	$ 2,372.3		$ 2,381.5
Transmission and Distribution Utilities [Member]
Revenues
Revenue from Contracts with Customers	1,179.8		1,141.2
Generation & Marketing [Member]
Revenues
Revenue from Contracts with Customers	439.7		477.5
Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	65		48.1
TOTAL REVENUES	50.8	[1]	28.5	[2]
Fuel and Other Consumables Used for Electric Generation [Member]
Expenses
Cost of Goods and Services Sold	550.4		501.8
Purchased Electricity for Resale [Member]
Expenses
Cost of Goods and Services Sold	861.8		990.3
AEP Texas Inc. [Member]
Revenues
Revenue from Contracts with Customers	351.8		354.1
Sales to AEP Affiliates	40.2		18.2
TOTAL REVENUES	390.7		371.6
Expenses
Other Operation	109.8		117
Maintenance	25.3		21.5
Depreciation and Amortization	138.9		110
Taxes Other Than Income Taxes	36.5		32.4
TOTAL EXPENSES	319.9		289.8
OPERATING INCOME (LOSS)	70.8		81.8
Other Income (Expense):
Interest Income	0.4		0.5
Allowance for Equity Funds Used During Construction	1.8		5.5
Non-Service Cost Components of Net Periodic Benefit Cost	2.8		3.1
Interest Expense	(37.4)		(35)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	38.4		55.9
Income Tax Expense (Benefit)	4		9.1
NET INCOME (LOSS)	34.4		46.8
AEP Texas Inc. [Member] | Transmission and Distribution Utilities [Member]
Revenues
Revenue from Contracts with Customers	349.8		352.4
AEP Texas Inc. [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	0.7		1
TOTAL REVENUES	39.8	[3]	17.8	[4]
AEP Texas Inc. [Member] | Fuel and Other Consumables Used for Electric Generation [Member]
Expenses
Cost of Goods and Services Sold	9.4		8.9
AEP Transmission Co [Member]
Revenues
Revenue from Contracts with Customers	245.2		187	[5]
Sales to AEP Affiliates	193.2		160.7	[6]
TOTAL REVENUES	243.5		191.7	[5],[6]
Expenses
Other Operation	17		16.6
Maintenance	3.2		2.6
Depreciation and Amortization	40.3		30.3
Taxes Other Than Income Taxes	41.4		31.1
TOTAL EXPENSES	101.9		80.6
OPERATING INCOME (LOSS)	141.6		111.1
Other Income (Expense):
Interest Income	0.7		0.4	[6]
Allowance for Equity Funds Used During Construction	11.3		14.9
Interest Expense	(21.7)		(20.3)	[6]
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	131.9		106.1
Income Tax Expense (Benefit)	27.6		22	[6]
NET INCOME (LOSS)	104.3		84.1	[6]
AEP Transmission Co [Member] | Transmission Revenues [Member]
Revenues
Revenue from Contracts with Customers	50.3		30.9	[6]
AEP Transmission Co [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	0		0.1	[6]
TOTAL REVENUES	0	[3]	0	[4],[5]
Appalachian Power Co [Member]
Revenues
Revenue from Contracts with Customers	788.4		826.3
Sales to AEP Affiliates	51.7		49.4
TOTAL REVENUES	792.8		820.4
Expenses
Other Operation	136.9		138.2
Maintenance	61.5		72
Depreciation and Amortization	112.5		108.5
Taxes Other Than Income Taxes	35.9		33.8
TOTAL EXPENSES	640.7		627.4
OPERATING INCOME (LOSS)	152.1		193
Other Income (Expense):
Interest Income	0.8		0.3
Carrying Costs Income	0		0.5
Allowance for Equity Funds Used During Construction	1.7		2.6
Non-Service Cost Components of Net Periodic Benefit Cost	4.3		4.5
Interest Expense	(49.3)		(47.4)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	109.6		153.5
Income Tax Expense (Benefit)	(24.1)		28
NET INCOME (LOSS)	133.7		125.5
Appalachian Power Co [Member] | Vertically Integrated Utilities [Member]
Revenues
Revenue from Contracts with Customers	738.7		767.5
Appalachian Power Co [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	2.4		3.5
TOTAL REVENUES	0	[3]	0	[4]
Appalachian Power Co [Member] | Fuel and Other Consumables Used for Electric Generation [Member]
Expenses
Cost of Goods and Services Sold	183.3		69
Appalachian Power Co [Member] | Purchased Electricity for Resale [Member]
Expenses
Cost of Goods and Services Sold	110.6		205.9
Indiana Michigan Power Co [Member]
Revenues
Revenue from Contracts with Customers	619.1		576.3
Sales to AEP Affiliates	2.3		4.7
Other Revenues - Affiliated	13.3		13.2
TOTAL REVENUES	614.3		576.8
Expenses
Purchased Electricity from AEP Affiliates	59.8		61.4
Other Operation	140.5		146.1
Maintenance	58.3		54.5
Depreciation and Amortization	86.2		59.3
Taxes Other Than Income Taxes	27.3		25
TOTAL EXPENSES	499.3		479.4
OPERATING INCOME (LOSS)	115		97.4
Other Income (Expense):
Carrying Costs Income	(0.7)		2.4
Other Income	5.7		4.4
Allowance for Equity Funds Used During Construction	6.2		1.8
Non-Service Cost Components of Net Periodic Benefit Cost	4.4		4.5
Interest Expense	(28.9)		(29.7)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	96.2		76.6
Income Tax Expense (Benefit)	(2.7)		12.4
NET INCOME (LOSS)	98.9		64.2
Indiana Michigan Power Co [Member] | Vertically Integrated Utilities [Member]
Revenues
Revenue from Contracts with Customers	596.7		553.9
Indiana Michigan Power Co [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	2		5
Sales to AEP Affiliates	15		15
TOTAL REVENUES	0	[3]	5.5	[4]
Indiana Michigan Power Co [Member] | Fuel and Other Consumables Used for Electric Generation [Member]
Expenses
Cost of Goods and Services Sold	57.6		77.5
Indiana Michigan Power Co [Member] | Purchased Electricity for Resale [Member]
Expenses
Cost of Goods and Services Sold	69.6		55.6
Ohio Power Co [Member]
Revenues
Revenue from Contracts with Customers	828.1		780.7
Sales to AEP Affiliates	7.5		3.1
TOTAL REVENUES	836.8		790.9
Expenses
Purchased Electricity from AEP Affiliates	46.1		30.2
Amortization Of Generation Deferrals	32.4		58.6
Other Operation	216.9		172.2
Maintenance	32.5		37.2
Depreciation and Amortization	63.3		64.8
Taxes Other Than Income Taxes	108.9		105.1
TOTAL EXPENSES	674.3		673.6
OPERATING INCOME (LOSS)	162.5		117.3
Other Income (Expense):
Interest Income	0.8		0.9
Carrying Costs Income	0.2		0.7
Allowance for Equity Funds Used During Construction	5.2		2.5
Non-Service Cost Components of Net Periodic Benefit Cost	3.7		3.9
Interest Expense	(24.6)		(25.2)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	147.8		100.1
Income Tax Expense (Benefit)	19.8		20.5
NET INCOME (LOSS)	128		79.6
Ohio Power Co [Member] | Transmission and Distribution Utilities [Member]
Revenues
Revenue from Contracts with Customers	826.5		786.3
Ohio Power Co [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	2.8		1.5
TOTAL REVENUES	5.1	[3]	3.9	[4]
Ohio Power Co [Member] | Purchased Electricity for Resale [Member]
Expenses
Cost of Goods and Services Sold	174.2		205.5
Public Service Co Of Oklahoma [Member]
Revenues
Revenue from Contracts with Customers	334		333.5
Sales to AEP Affiliates	1.6		1.1
TOTAL REVENUES	332.8		336.8
Expenses
Other Operation	73.6		86.8
Maintenance	22.5		26.9
Depreciation and Amortization	43.5		36.8
Taxes Other Than Income Taxes	11.4		11.6
TOTAL EXPENSES	311.9		332.9
OPERATING INCOME (LOSS)	20.9		3.9
Other Income (Expense):
Other Income	0.1		0
Allowance for Equity Funds Used During Construction	0.1		(0.1)
Non-Service Cost Components of Net Periodic Benefit Cost	2.1		2.2
Interest Expense	(16.9)		(14.7)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	6.2		(8.6)
Income Tax Expense (Benefit)	0		(1.4)
NET INCOME (LOSS)	6.2		(7.2)
Public Service Co Of Oklahoma [Member] | Vertically Integrated Utilities [Member]
Revenues
Revenue from Contracts with Customers	329.2		335.1
Public Service Co Of Oklahoma [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	2		0.6
TOTAL REVENUES	0	[3]	0	[4]
Public Service Co Of Oklahoma [Member] | Fuel and Other Consumables Used for Electric Generation [Member]
Expenses
Cost of Goods and Services Sold	38		48.4
Public Service Co Of Oklahoma [Member] | Purchased Electricity for Resale [Member]
Expenses
Cost of Goods and Services Sold	122.9		122.4
Southwestern Electric Power Co [Member]
Revenues
Revenue from Contracts with Customers	426.4		419.7
Sales to AEP Affiliates	6.4		6.1
TOTAL REVENUES	421.1		419.4
Expenses
Other Operation	84.6		94.9
Maintenance	28.9		31
Depreciation and Amortization	62.1		57.4
Taxes Other Than Income Taxes	25.3		25
TOTAL EXPENSES	367		377.8
OPERATING INCOME (LOSS)	54.1		41.6
Other Income (Expense):
Interest Income	0.7		1.8
Allowance for Equity Funds Used During Construction	1.8		2.3
Non-Service Cost Components of Net Periodic Benefit Cost	2.1		2.3
Interest Expense	(29.7)		(32.2)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	29		15.8
Income Tax Expense (Benefit)	0.7		2.9
Equity Earnings (Loss) of Unconsolidated Subsidiaries	0.7		0.5
NET INCOME (LOSS)	29		13.4
Net Income Attributable to Noncontrolling Interests	1.2		1.6
EARNINGS ATTRIBUTABLE TO COMMON SHAREHOLDERS	27.8		11.8
Southwestern Electric Power Co [Member] | Vertically Integrated Utilities [Member]
Revenues
Revenue from Contracts with Customers	414.3		413
Southwestern Electric Power Co [Member] | Other Revenues [Member]
Revenues
Revenue from Contracts with Customers	0.4		0.3
TOTAL REVENUES	0	[3]	0	[4]
Southwestern Electric Power Co [Member] | Fuel and Other Consumables Used for Electric Generation [Member]
Expenses
Cost of Goods and Services Sold	133.5		126.8
Southwestern Electric Power Co [Member] | Purchased Electricity for Resale [Member]
Expenses
Cost of Goods and Services Sold	$ 32.6		$ 42.7
[1]	Amounts include affiliated and nonaffiliated revenues.
[2]	Amounts include affiliated and nonaffiliated revenues.
[3]	Amounts include affiliated and nonaffiliated revenues.
[4]	Amounts include affiliated and nonaffiliated revenues.
[5]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[6]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net Income (Loss)	$ 574.1	$ 456.7
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	(28.9)	2.7
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(1.4)	(1.4)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	(30.3)	1.3
TOTAL COMPREHENSIVE INCOME (LOSS)	543.8	458
Total Comprehensive Income Attributable to Noncontrolling Interest	1.3	2.3
TOTAL COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO COMMON SHAREHOLDERS	542.5	455.7
AEP Texas Inc. [Member]
Net Income (Loss)	34.4	46.8
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	0.3	0.2
Amortization of Pension and OPEB Deferred Costs, Net of Tax	0	0.1
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	0.3	0.3
TOTAL COMPREHENSIVE INCOME (LOSS)	34.7	47.1
Appalachian Power Co [Member]
Net Income (Loss)	133.7	125.5
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	(0.2)	(0.2)
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(0.6)	(0.8)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	(0.8)	(1)
TOTAL COMPREHENSIVE INCOME (LOSS)	132.9	124.5
Indiana Michigan Power Co [Member]
Net Income (Loss)	98.9	64.2
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	0.4	0.4
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	0.4	0.4
TOTAL COMPREHENSIVE INCOME (LOSS)	99.3	64.6
Ohio Power Co [Member]
Net Income (Loss)	128	79.6
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	(0.3)	(0.3)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	(0.3)	(0.3)
TOTAL COMPREHENSIVE INCOME (LOSS)	127.7	79.3
Public Service Co Of Oklahoma [Member]
Net Income (Loss)	6.2	(7.2)
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	(0.2)	(0.2)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	(0.2)	(0.2)
TOTAL COMPREHENSIVE INCOME (LOSS)	6	(7.4)
Southwestern Electric Power Co [Member]
Net Income (Loss)	29	13.4
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	0.4	0.4
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(0.3)	(0.3)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	0.1	0.1
TOTAL COMPREHENSIVE INCOME (LOSS)	29.1	13.5
Total Comprehensive Income Attributable to Noncontrolling Interest	1.2	1.6
TOTAL COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 27.9	$ 11.9

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flow Hedges, Tax	$ (7.7)	$ 0.7
Amortization of Pension and OPEB Deferred Costs, Tax	(0.4)	(0.4)
AEP Texas Inc. [Member]
Cash Flow Hedges, Tax	0.1	0.1
Amortization of Pension and OPEB Deferred Costs, Tax	0	0
Appalachian Power Co [Member]
Cash Flow Hedges, Tax	(0.1)	(0.1)
Amortization of Pension and OPEB Deferred Costs, Tax	(0.2)	(0.2)
Indiana Michigan Power Co [Member]
Cash Flow Hedges, Tax	0.1	0.1
Ohio Power Co [Member]
Cash Flow Hedges, Tax	(0.1)	(0.1)
Public Service Co Of Oklahoma [Member]
Cash Flow Hedges, Tax	(0.1)	(0.1)
Southwestern Electric Power Co [Member]
Cash Flow Hedges, Tax	0.1	0.1
Amortization of Pension and OPEB Deferred Costs, Tax	$ (0.1)	$ (0.1)

Condensed Consolidated Statemen

Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Total	AEP Transmission Co [Member]		AEP Texas Inc. [Member]	Appalachian Power Co [Member]	Indiana Michigan Power Co [Member]	Ohio Power Co [Member]	Public Service Co Of Oklahoma [Member]	Southwestern Electric Power Co [Member]	Common Stock [Member]	Common Stock [Member]Appalachian Power Co [Member]	Common Stock [Member]Indiana Michigan Power Co [Member]	Common Stock [Member]Ohio Power Co [Member]	Common Stock [Member]Public Service Co Of Oklahoma [Member]	Common Stock [Member]Southwestern Electric Power Co [Member]	Additional Paid-in Capital [Member]		Additional Paid-in Capital [Member]AEP Transmission Co [Member]	Additional Paid-in Capital [Member]AEP Texas Inc. [Member]	Additional Paid-in Capital [Member]Appalachian Power Co [Member]	Additional Paid-in Capital [Member]Indiana Michigan Power Co [Member]	Additional Paid-in Capital [Member]Ohio Power Co [Member]	Additional Paid-in Capital [Member]Public Service Co Of Oklahoma [Member]	Additional Paid-in Capital [Member]Southwestern Electric Power Co [Member]	Retained Earnings [Member]	Retained Earnings [Member]AEP Transmission Co [Member]	Retained Earnings [Member]AEP Texas Inc. [Member]	Retained Earnings [Member]Appalachian Power Co [Member]	Retained Earnings [Member]Indiana Michigan Power Co [Member]	Retained Earnings [Member]Ohio Power Co [Member]	Retained Earnings [Member]Public Service Co Of Oklahoma [Member]	Retained Earnings [Member]Southwestern Electric Power Co [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Other Comprehensive Income [Member]AEP Texas Inc. [Member]	Accumulated Other Comprehensive Income [Member]Appalachian Power Co [Member]	Accumulated Other Comprehensive Income [Member]Indiana Michigan Power Co [Member]	Accumulated Other Comprehensive Income [Member]Ohio Power Co [Member]	Accumulated Other Comprehensive Income [Member]Public Service Co Of Oklahoma [Member]	Accumulated Other Comprehensive Income [Member]Southwestern Electric Power Co [Member]	Noncontrolling Interests [Member]	Noncontrolling Interests [Member]Southwestern Electric Power Co [Member]	Additional Paid-in Capital [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.62
Beginning Balance, Shares at Dec. 31, 2017										512,200,000
Beginning Balance at Dec. 31, 2017	$ 18,313.6			$ 2,169.9	$ 3,804.5	$ 2,217.6	$ 2,310.3	$ 1,215.3	$ 2,234.5	$ 3,329.4	$ 260.4	$ 56.6	$ 321.2	$ 157.2	$ 135.7	$ 6,398.7			$ 1,057.9	$ 1,828.7	$ 980.9	$ 838.8	$ 364	$ 676.6	$ 8,626.7		$ 1,124.6	$ 1,714.1	$ 1,192.2	$ 1,148.4	$ 691.5	$ 1,426.6	$ (67.8)	$ (12.6)	$ 1.3	$ (12.1)	$ 1.9	$ 2.6	$ (4)	$ 26.6	$ (0.4)
Members' Equity at Dec. 31, 2017		$ 2,589.9																$ 1,816.6								$ 773.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock, Value	32.2									$ 3.3						28.9
Issuance of Common Stock, Shares										500,000
Common Stock Dividends	(306.1)																								(305.5)
Common Stock Dividends					(40)	(33.5)	(112.5)	(12.5)	(20)																			(40)	(33.5)	(112.5)	(12.5)	(20)
Common Stock Dividends									(0.8)																															(0.6)	(0.8)
Other Changes in Equity	16.9															16.9																										$ 0
Capital Contributions from Parent		65		100														65	100
ASU 2018-02 Adoption	(3)			(0.9)	0.4	(2.4)	0.4	0.5	(1.3)																14		1.8	0.1	0.3			(0.4)	(17)	(2.7)	0.3	(2.7)	0.4	0.5	(0.9)
ASU 2016-01 Adoption	0																								11.9								(11.9)
Net Income (Loss)	454.4								11.8																454.4							11.8
Net Income Attributable to Noncontrolling Interests	2.3								1.6																															2.3	1.6
Net Income (Loss)	456.7	84.1	[1]	46.8	125.5	64.2	79.6	(7.2)	13.4																	84.1	46.8	125.5	64.2	79.6	(7.2)
Other Comprehensive Income (Loss)	1.3			0.3	(1)	0.4	(0.3)	(0.2)	0.1																								1.3	0.3	(1)	0.4	(0.3)	(0.2)	0.1
Ending Balance at Mar. 31, 2018	$ 18,511.6			2,316.1	3,889.4	2,246.3	2,277.5	$ 1,195.9	2,225.9	$ 3,332.7	260.4	56.6	321.2	157.2	135.7	6,444.5			1,157.9	1,828.7	980.9	838.8	364	676.6	8,801.5		1,173.2	1,799.7	1,223.2	1,115.5	671.8	1,418	(95.4)	(15)	0.6	(14.4)	2	2.9	(4.8)	28.3	0.4
Members' Equity at Mar. 31, 2018		2,739																1,881.6								857.4
Ending Balance, Shares at Mar. 31, 2018										512,700,000
Common Stock, Dividends, Per Share, Declared	$ 0.67
Beginning Balance, Shares at Dec. 31, 2018	513,450,036							10,482,000		513,500,000
Beginning Balance at Dec. 31, 2018	$ 19,059.4			2,580.5	4,006.1	2,352.8	2,297.4	$ 1,248	2,315.6	$ 3,337.4	260.4	56.6	321.2	157.2	135.7	6,486.1			1,257.9	1,828.7	980.9	838.8	364	676.6	9,325.3		1,337.7	1,922	1,329.1	1,136.4	724.7	1,508.4	(120.4)	(15.1)	(5)	(13.8)	1	2.1	(5.4)	31	0.3
Members' Equity at Dec. 31, 2018		3,569.8																2,480.6								1,089.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock, Value	14.5									$ 1.2						13.3
Issuance of Common Stock, Shares										100,000
Common Stock Dividends	(333.6)																								(332.5)
Common Stock Dividends					(50)	(20)	(25)	(11.3)	(18.7)																			(50)	(20)	(25)	(11.3)	(18.7)
Common Stock Dividends									(1.1)																															(1.1)	(1.1)
Other Changes in Equity	(55.6)															(56.6)	[2]																							1		$ 62.1	[2]
Capital Contributions from Parent		0		200															200
Net Income (Loss)	572.8								27.8																572.8							27.8
Net Income Attributable to Noncontrolling Interests	1.3								1.2																															1.3	1.2
Net Income (Loss)	574.1	104.3		34.4	133.7	98.9	128	6.2	29																	104.3	34.4	133.7	98.9	128	6.2
Other Comprehensive Income (Loss)	(30.3)			0.3	(0.8)	0.4	(0.3)	(0.2)	0.1																								(30.3)	0.3	(0.8)	0.4	(0.3)	(0.2)	0.1
Ending Balance at Mar. 31, 2019	$ 19,228.5			$ 2,815.2	$ 4,089	$ 2,432.1	$ 2,400.1	$ 1,242.7	$ 2,324.9	$ 3,338.6	$ 260.4	$ 56.6	$ 321.2	$ 157.2	$ 135.7	$ 6,442.8			$ 1,457.9	$ 1,828.7	$ 980.9	$ 838.8	$ 364	$ 676.6	$ 9,565.6		$ 1,372.1	$ 2,005.7	$ 1,408	$ 1,239.4	$ 719.6	$ 1,517.5	$ (150.7)	$ (14.8)	$ (5.8)	$ (13.4)	$ 0.7	$ 1.9	$ (5.3)	$ 32.2	$ 0.4
Members' Equity at Mar. 31, 2019		$ 3,674.1																$ 2,480.6								$ 1,193.5
Ending Balance, Shares at Mar. 31, 2019	513,632,124							10,482,000		513,600,000
[1]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[2]	Includes $(62) million related to a forward equity purchase contract associated with the issuance of Equity Units. See “Equity Units” section of Footnote 13

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Dec. 31, 2018
Document Period End Date		Mar. 31, 2019
Current Assets
Cash and Cash Equivalents		$ 227.7	$ 234.1
Restricted Cash		135.4	210
Other Temporary Investments		168.9	159.1
Accounts Receivable:
Customers		696.6	699
Accrued Unbilled Revenues		207.8	209.3
Pledged Accounts Receivable - AEP Credit		970.5	999.8
Miscellaneous		48.3	55.2
Allowance for Uncollectible Accounts		(40.9)	(36.8)
Total Accounts Receivable		1,882.3	1,926.5
Fuel		360.3	341.5
Materials and Supplies		586.3	579.6
Risk Management Assets		93.9	162.8
Regulatory Asset for Under-Recovered Fuel Costs		123.3	150.1
Margin Deposits		136.3	141.4
Prepayments and Other Current Assets		200.4	208.8
TOTAL CURRENT ASSETS		3,914.8	4,113.9
Property, Plant and Equipment
Generation		21,780.6	21,699.9
Transmission		21,773.5	21,531
Distribution		21,483.5	21,195.4
Other Property, Plant and Equipment		4,202.7	4,265
Construction Work in Progress		4,910.9	4,393.9
Total Property, Plant and Equipment		74,151.2	73,085.2
Accumulated Depreciation and Amortization		18,182.6	17,986.1
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		55,968.6	55,099.1
Other Noncurrent Assets
Regulatory Assets		3,297.9	3,310.4
Securitized Assets		853	920.6
Spent Nuclear Fuel and Decommissioning Trusts		2,684	2,474.9
Goodwill		52.5	52.5
Long-term Risk Management Assets		250.4	254
Operating Lease Assets		1,045.4	0
Deferred Charges and Other Noncurrent Assets		2,655.4	2,577.4
TOTAL OTHER NONCURRENT ASSETS		10,838.6	9,589.8
TOTAL ASSETS		70,722	68,802.8
Current Liabilities
Accounts Payable		1,497.2	1,874.3
Short-term Debt:
Securitized Debt for Receivables - AEP Credit	[1]	750	750
Other Short-term Debt		1,108	1,160
Total Short-term Debt		1,858	1,910
Long-term Debt Due Within One Year		1,528.5	1,698.5
Risk Management Liabilities		63.4	55
Customer Deposits		400.4	412.2
Accrued Taxes		1,156.5	1,218
Accrued Interest		306	231.7
Obligations Under Operating Leases		228.2	0
Regulatory Liability for Over-Recovered Fuel Costs		64.3	58.6
Other Current Liabilities		888.1	1,190.5
TOTAL CURRENT LIABILITIES		7,990.6	8,648.8
Noncurrent Liabilities
Long-term Debt		22,898.2	21,648.2
Long-term Debt - Affiliated		0	0
Long-term Risk Management Liabilities		267.9	263.4
Deferred Income Taxes		7,193	7,086.5
Regulatory Liabilities and Deferred Investment Tax Credits		8,669.8	8,540.3
Asset Retirement Obligations		2,317.3	2,287.7
Employee Benefits and Pension Obligations		383.9	377.1
Obligations Under Operating Leases		860.2	0
Deferred Credits and Other Noncurrent Liabilities		797.9	782.6
TOTAL NONCURRENT LIABILITIES		43,388.2	40,985.8
TOTAL LIABILITIES		51,378.8	49,634.6
Rate Matters
Commitments and Contingencies
Redeemable Noncontrolling Interest		68.5	69.4
Contingently Redeemable Performance Share Awards		46.2	39.4
Total Mezzanine Equity		114.7	108.8
Equity
Common Stock		3,338.6	3,337.4
Paid-in Capital		6,442.8	6,486.1
Retained Earnings		9,565.6	9,325.3
Accumulated Other Comprehensive Income (Loss)		(150.7)	(120.4)
TOTAL COMMON SHAREHOLDER'S EQUITY		19,196.3	19,028.4
Noncontrolling Interests		32.2	31
TOTAL EQUITY		19,228.5	19,059.4
TOTAL LIABILITIES AND EQUITY		70,722	68,802.8
AEP Texas Inc. [Member]
Current Assets
Cash and Cash Equivalents		0.1	3.1
Restricted Cash		100.6	156.7
Advances to Affiliates		7.7	8
Accounts Receivable:
Customers		125.5	110.9
Affiliated Companies		15.9	15
Accrued Unbilled Revenues		63	70.4
Miscellaneous		1.8	1.9
Allowance for Uncollectible Accounts		(1.5)	(1.3)
Total Accounts Receivable		204.7	196.9
Fuel		8.5	8.8
Materials and Supplies		54.1	52.8
Accrued Tax Benefits		24.3	44.9
Prepayments and Other Current Assets		4.8	5.3
TOTAL CURRENT ASSETS		404.8	476.5
Property, Plant and Equipment
Generation		352	352.1
Transmission		3,777.7	3,683.6
Distribution		4,100.6	4,043.2
Other Property, Plant and Equipment		734.5	727.9
Construction Work in Progress		941.8	836.2
Total Property, Plant and Equipment		9,906.6	9,643
Accumulated Depreciation and Amortization		1,686.6	1,651.2
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		8,220	7,991.8
Other Noncurrent Assets
Regulatory Assets		426.7	430
Securitized Assets		592.9	649.1
Deferred Charges and Other Noncurrent Assets		212	56.3
TOTAL OTHER NONCURRENT ASSETS		1,231.6	1,135.4
TOTAL ASSETS		9,856.4	9,603.7
Current Liabilities
Advances from Affiliates		271.2	216
Accounts Payable		242	276.5
Affiliated Companies		22.6	30.3
Short-term Debt:
Long-term Debt Due Within One Year		508.6	501.1
Risk Management Liabilities		0.2	0.2
Accrued Taxes		112.4	75.5
Accrued Interest		50.7	37.3
Oklaunion Purchase Power Agreement - Current		25.8	24.3
Obligations Under Operating Leases		12.2	0
Other Current Liabilities		82.4	98.3
TOTAL CURRENT LIABILITIES		1,328.1	1,259.5
Noncurrent Liabilities
Long-term Debt		3,269.7	3,380.2
Deferred Income Taxes		908.8	913.1
Regulatory Liabilities and Deferred Investment Tax Credits		1,344.1	1,344.3
Oklaunion Purchase Power Agreement		15.1	22.1
Obligations Under Operating Leases		70.2	0
Deferred Credits and Other Noncurrent Liabilities		105.2	104
TOTAL NONCURRENT LIABILITIES		5,713.1	5,763.7
TOTAL LIABILITIES		7,041.2	7,023.2
Rate Matters
Commitments and Contingencies
Equity
Paid-in Capital		1,457.9	1,257.9
Retained Earnings		1,372.1	1,337.7
Accumulated Other Comprehensive Income (Loss)		(14.8)	(15.1)
TOTAL EQUITY		2,815.2	2,580.5
TOTAL LIABILITIES AND EQUITY		9,856.4	9,603.7
AEP Transmission Co [Member]
Current Assets
Cash and Cash Equivalents		0	0
Advances to Affiliates		73.5	96.9
Accounts Receivable:
Customers		19	11.8
Affiliated Companies		68.8	61
Miscellaneous		0.2	0
Total Accounts Receivable		88	72.8
Materials and Supplies		19.6	19
Accrued Tax Benefits		19.1	33.4
Prepayments and Other Current Assets		2.9	3.4
TOTAL CURRENT ASSETS		203.1	225.5
Property, Plant and Equipment
Transmission		6,580.6	6,515.8
Other Property, Plant and Equipment		174.4	174
Construction Work in Progress		1,812.2	1,578.3
Total Property, Plant and Equipment		8,567.2	8,268.1
Accumulated Depreciation and Amortization		306.7	271.9
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		8,260.5	7,996.2
Other Noncurrent Assets
Regulatory Assets		10.5	12.9
Deferred Tax Assets, Property, Plant and Equipment		134.7	157.9
Deferred Charges and Other Noncurrent Assets		7.3	1.6
TOTAL OTHER NONCURRENT ASSETS		152.5	172.4
TOTAL ASSETS		8,616.1	8,394.1
Current Liabilities
Advances from Affiliates		223.1	45.4
Accounts Payable		258	347.2
Affiliated Companies		67	56
Short-term Debt:
Long-term Debt Due Within One Year		85	85
Accrued Taxes		242.5	288.9
Accrued Interest		35.1	15.9
Obligations Under Operating Leases		2.6	0
Other Current Liabilities		20.3	3.8
TOTAL CURRENT LIABILITIES		933.6	842.2
Noncurrent Liabilities
Long-term Debt		2,738.4	2,738
Deferred Income Taxes		721.9	704.4
Regulatory Liabilities and Deferred Investment Tax Credits		527.9	521.3
Obligations Under Operating Leases		3.2	0
Deferred Credits and Other Noncurrent Liabilities		17	18.4
TOTAL NONCURRENT LIABILITIES		4,008.4	3,982.1
TOTAL LIABILITIES		4,942	4,824.3
Rate Matters
Commitments and Contingencies
Equity
Members' Capital		2,480.6	2,480.6
Retained Earnings		1,193.5	1,089.2
Members' Equity		3,674.1	3,569.8
TOTAL LIABILITIES AND EQUITY		8,616.1	8,394.1
Appalachian Power Co [Member]
Current Assets
Cash and Cash Equivalents		2.9	4.2
Restricted Cash		18.3	25.6
Advances to Affiliates		216.6	23
Accounts Receivable:
Customers		144.4	146.5
Affiliated Companies		60.3	73.4
Accrued Unbilled Revenues		61.7	63.5
Miscellaneous		1.1	2.3
Allowance for Uncollectible Accounts		(2.8)	(2.3)
Total Accounts Receivable		264.7	283.4
Fuel		69.9	61.3
Materials and Supplies		102.1	100.1
Risk Management Assets		12.9	57.2
Regulatory Asset for Under-Recovered Fuel Costs		78.8	99.6
Prepayments and Other Current Assets		33.9	44.3
TOTAL CURRENT ASSETS		800.1	698.7
Property, Plant and Equipment
Generation		6,531.5	6,509.6
Transmission		3,330.1	3,317.7
Distribution		4,014.6	3,989.4
Other Property, Plant and Equipment		504.5	485.8
Construction Work in Progress		524.9	490.2
Total Property, Plant and Equipment		14,905.6	14,792.7
Accumulated Depreciation and Amortization		4,174.9	4,124.4
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		10,730.7	10,668.3
Other Noncurrent Assets
Regulatory Assets		469.6	475.8
Securitized Assets		252.7	258.7
Long-term Risk Management Assets		0.3	0.9
Operating Lease Assets		79.1	0
Deferred Charges and Other Noncurrent Assets		194.9	188.1
TOTAL OTHER NONCURRENT ASSETS		996.6	923.5
TOTAL ASSETS		12,527.4	12,290.5
Current Liabilities
Advances from Affiliates		0	205.6
Accounts Payable		218.7	263.8
Affiliated Companies		80.8	84
Short-term Debt:
Long-term Debt Due Within One Year		345	430.7
Risk Management Liabilities		6.1	0.4
Customer Deposits		88.3	88.4
Accrued Taxes		92.3	89.3
Accrued Interest		74.2	41.5
Obligations Under Operating Leases		15	0
Other Current Liabilities		103.7	150.3
TOTAL CURRENT LIABILITIES		1,024.1	1,354
Noncurrent Liabilities
Long-term Debt		4,099	3,631.9
Long-term Risk Management Liabilities		0.2	0.2
Deferred Income Taxes		1,615.4	1,625.8
Regulatory Liabilities and Deferred Investment Tax Credits		1,415.7	1,449.7
Asset Retirement Obligations		106.2	107.1
Employee Benefits and Pension Obligations		54.3	57.1
Obligations Under Operating Leases		64.8	0
Deferred Credits and Other Noncurrent Liabilities		58.7	58.6
TOTAL NONCURRENT LIABILITIES		7,414.3	6,930.4
TOTAL LIABILITIES		8,438.4	8,284.4
Rate Matters
Commitments and Contingencies
Equity
Common Stock		260.4	260.4
Paid-in Capital		1,828.7	1,828.7
Retained Earnings		2,005.7	1,922
Accumulated Other Comprehensive Income (Loss)		(5.8)	(5)
TOTAL EQUITY		4,089	4,006.1
TOTAL LIABILITIES AND EQUITY		12,527.4	12,290.5
Indiana Michigan Power Co [Member]
Current Assets
Cash and Cash Equivalents		1.7	2.4
Advances to Affiliates		12.8	12.7
Accounts Receivable:
Customers		62.9	63.1
Affiliated Companies		55.4	75
Accrued Unbilled Revenues		8.1	3.6
Miscellaneous		1.2	1.4
Allowance for Uncollectible Accounts		(0.2)	(0.1)
Total Accounts Receivable		127.4	143
Fuel		32	37.3
Materials and Supplies		166.1	167.3
Risk Management Assets		4.4	8.6
Accrued Tax Benefits		12	26.6
Accrued Reimbursement of Spent Nuclear Fuel Costs		23.5	7.9
Prepayments and Other Current Assets		23.4	24.6
TOTAL CURRENT ASSETS		403.3	430.4
Property, Plant and Equipment
Generation		4,895	4,887.2
Transmission		1,588.9	1,576.8
Distribution		2,291.5	2,249.7
Other Property, Plant and Equipment		580.1	583.8
Construction Work in Progress		533.5	465.3
Total Property, Plant and Equipment		9,889	9,762.8
Accumulated Depreciation and Amortization		3,208.4	3,151.6
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		6,680.6	6,611.2
Other Noncurrent Assets
Regulatory Assets		504.7	512.5
Spent Nuclear Fuel and Decommissioning Trusts		2,684	2,474.9
Long-term Risk Management Assets		0.1	0.6
Operating Lease Assets		326.3	0
Deferred Charges and Other Noncurrent Assets		171	193
TOTAL OTHER NONCURRENT ASSETS		3,686.1	3,181
TOTAL ASSETS		10,770	10,222.6
Current Liabilities
Advances from Affiliates		34.7	1.1
Accounts Payable		160.3	174.7
Affiliated Companies		70.4	70.2
Short-term Debt:
Long-term Debt Due Within One Year		140.4	155.4
Risk Management Liabilities		0.3	0.3
Customer Deposits		38.6	38
Accrued Taxes		101.7	90.7
Accrued Interest		20.9	37.3
Obligations Under Operating Leases		81.8	0
Regulatory Liability for Over-Recovered Fuel Costs		22.2	27.4
Other Current Liabilities		68.2	103
TOTAL CURRENT LIABILITIES		739.5	698.1
Noncurrent Liabilities
Long-term Debt		2,871	2,880
Long-term Risk Management Liabilities		0.1	0.1
Deferred Income Taxes		951.1	948
Regulatory Liabilities and Deferred Investment Tax Credits		1,743.5	1,574.5
Asset Retirement Obligations		1,697.8	1,681.3
Obligations Under Operating Leases		266	0
Deferred Credits and Other Noncurrent Liabilities		68.9	87.8
TOTAL NONCURRENT LIABILITIES		7,598.4	7,171.7
TOTAL LIABILITIES		8,337.9	7,869.8
Rate Matters
Commitments and Contingencies
Equity
Common Stock		56.6	56.6
Paid-in Capital		980.9	980.9
Retained Earnings		1,408	1,329.1
Accumulated Other Comprehensive Income (Loss)		(13.4)	(13.8)
TOTAL EQUITY		2,432.1	2,352.8
TOTAL LIABILITIES AND EQUITY		10,770	10,222.6
Ohio Power Co [Member]
Current Assets
Cash and Cash Equivalents		3.3	4.9
Restricted Cash		16.5	27.6
Accounts Receivable:
Customers		89.4	111.1
Affiliated Companies		55.9	70.8
Accrued Unbilled Revenues		27.1	21.4
Miscellaneous		0.4	0.3
Allowance for Uncollectible Accounts		(0.6)	(1)
Total Accounts Receivable		172.2	202.6
Materials and Supplies		42.9	42.9
Renewable Energy Credits		27.1	25.9
Prepayments and Other Current Assets		15.1	15.7
TOTAL CURRENT ASSETS		277.1	319.6
Property, Plant and Equipment
Transmission		2,551.7	2,544.3
Distribution		5,026.6	4,942.3
Other Property, Plant and Equipment		580	574.8
Construction Work in Progress		461	432.1
Total Property, Plant and Equipment		8,619.3	8,493.5
Accumulated Depreciation and Amortization		2,224.1	2,218.6
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		6,395.2	6,274.9
Other Noncurrent Assets
Regulatory Assets		375	387.5
Securitized Assets		7.3	12.9
Deferred Charges and Other Noncurrent Assets		464.2	441
TOTAL OTHER NONCURRENT ASSETS		846.5	841.4
TOTAL ASSETS		7,518.8	7,435.9
Current Liabilities
Advances from Affiliates		227.6	114.1
Accounts Payable		177.7	211.9
Affiliated Companies		91.1	102.9
Short-term Debt:
Long-term Debt Due Within One Year		24.6	47.9
Risk Management Liabilities		6.9	5.8
Customer Deposits		103.1	113.1
Accrued Taxes		423.4	537.8
Obligations Under Operating Leases		13	0
Other Current Liabilities		147.2	214.2
TOTAL CURRENT LIABILITIES		1,214.6	1,347.7
Noncurrent Liabilities
Long-term Debt		1,669	1,668.7
Long-term Risk Management Liabilities		99.4	93.8
Deferred Income Taxes		782.3	763.3
Regulatory Liabilities and Deferred Investment Tax Credits		1,234.4	1,221.2
Obligations Under Operating Leases		74	0
Deferred Credits and Other Noncurrent Liabilities		45	43.8
TOTAL NONCURRENT LIABILITIES		3,904.1	3,790.8
TOTAL LIABILITIES		5,118.7	5,138.5
Rate Matters
Commitments and Contingencies
Equity
Common Stock		321.2	321.2
Paid-in Capital		838.8	838.8
Retained Earnings		1,239.4	1,136.4
Accumulated Other Comprehensive Income (Loss)		0.7	1
TOTAL EQUITY		2,400.1	2,297.4
TOTAL LIABILITIES AND EQUITY		7,518.8	7,435.9
Public Service Co Of Oklahoma [Member]
Current Assets
Cash and Cash Equivalents		1.5	2
Accounts Receivable:
Customers		35.7	32.5
Affiliated Companies		24.3	26.2
Miscellaneous		3.6	5.7
Allowance for Uncollectible Accounts		(0.4)	(0.1)
Total Accounts Receivable		63.2	64.3
Fuel		10	12.3
Materials and Supplies		43.9	44.8
Risk Management Assets		5	10.4
Accrued Tax Benefits		9.5	14.7
Prepayments and Other Current Assets		12.7	9.4
TOTAL CURRENT ASSETS		145.8	157.9
Property, Plant and Equipment
Generation		1,568.6	1,577
Transmission		899.8	892.3
Distribution		2,600.1	2,572.8
Other Property, Plant and Equipment		306	303.5
Construction Work in Progress		98.6	94
Total Property, Plant and Equipment		5,473.1	5,439.6
Accumulated Depreciation and Amortization		1,496.2	1,472.9
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		3,976.9	3,966.7
Other Noncurrent Assets
Regulatory Assets		365.1	369
Operating Lease Assets		34.8	0
Employee Benefits and Pension Assets		32	31.7
Deferred Charges and Other Noncurrent Assets		37.9	7.1
TOTAL OTHER NONCURRENT ASSETS		469.8	407.8
TOTAL ASSETS		4,592.5	4,532.4
Current Liabilities
Advances from Affiliates		55.2	105.5
Accounts Payable		90.1	126.9
Affiliated Companies		45.9	47.1
Short-term Debt:
Long-term Debt Due Within One Year		375.5	375.5
Risk Management Liabilities		0.7	1
Customer Deposits		59.2	58.6
Accrued Taxes		42.5	22.4
Obligations Under Operating Leases		5.7	0
Regulatory Liability for Over-Recovered Fuel Costs		17.7	20.1
Other Current Liabilities		63.5	64.5
TOTAL CURRENT LIABILITIES		756	821.6
Noncurrent Liabilities
Long-term Debt		1,010.7	911.5
Deferred Income Taxes		610.6	607.8
Regulatory Liabilities and Deferred Investment Tax Credits		861.2	864.7
Asset Retirement Obligations		47.9	46.3
Obligations Under Operating Leases		29.1	0
Deferred Credits and Other Noncurrent Liabilities		34.3	32.5
TOTAL NONCURRENT LIABILITIES		2,593.8	2,462.8
TOTAL LIABILITIES		3,349.8	3,284.4
Rate Matters
Commitments and Contingencies
Equity
Common Stock		157.2	157.2
Paid-in Capital		364	364
Retained Earnings		719.6	724.7
Accumulated Other Comprehensive Income (Loss)		1.9	2.1
TOTAL EQUITY		1,242.7	1,248
TOTAL LIABILITIES AND EQUITY		4,592.5	4,532.4
Southwestern Electric Power Co [Member]
Current Assets
Cash and Cash Equivalents		22.1	24.5
Advances to Affiliates		2	83.4
Accounts Receivable:
Customers		32	24.5
Affiliated Companies		20	28.8
Miscellaneous		18.2	20.2
Allowance for Uncollectible Accounts		(1.2)	(0.7)
Total Accounts Receivable		69	72.8
Fuel		135.1	120.5
Materials and Supplies		69.1	67.5
Risk Management Assets		2	4.8
Regulatory Asset for Under-Recovered Fuel Costs		15.6	18.8
Prepayments and Other Current Assets		31.3	22.2
TOTAL CURRENT ASSETS		346.2	414.5
Property, Plant and Equipment
Generation		4,711.6	4,672.6
Transmission		1,907.2	1,866.9
Distribution		2,204.9	2,178.6
Other Property, Plant and Equipment		658.9	762.7
Construction Work in Progress		193.4	199.3
Total Property, Plant and Equipment		9,676	9,680.1
Accumulated Depreciation and Amortization		2,760.6	2,808.3
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		6,915.4	6,871.8
Other Noncurrent Assets
Regulatory Assets		226.6	230.8
Deferred Charges and Other Noncurrent Assets		193.8	111.2
TOTAL OTHER NONCURRENT ASSETS		420.4	342
TOTAL ASSETS		7,682	7,628.3
Current Liabilities
Advances from Affiliates		74	0
Accounts Payable		98.6	129.1
Affiliated Companies		45.8	64.2
Short-term Debt:
Long-term Debt Due Within One Year		6.2	59.7
Risk Management Liabilities		0.2	0.4
Customer Deposits		65.6	64.5
Accrued Taxes		91.1	42.8
Accrued Interest		22	34.7
Obligations Under Finance Leases		10.6	10.2
Obligations Under Operating Leases		6.1	0
Other Current Liabilities		87	107.3
TOTAL CURRENT LIABILITIES		507.2	512.9
Noncurrent Liabilities
Long-term Debt		2,652.9	2,653.7
Long-term Risk Management Liabilities		1.9	2.2
Deferred Income Taxes		910.1	902.8
Regulatory Liabilities and Deferred Investment Tax Credits		922.7	923
Asset Retirement Obligations		197	191.3
Employee Benefits and Pension Obligations		23.7	24.8
Obligations Under Finance Leases		49.3	50.6
Obligations Under Operating Leases		32.3	0
Deferred Credits and Other Noncurrent Liabilities		60	51.4
TOTAL NONCURRENT LIABILITIES		4,849.9	4,799.8
TOTAL LIABILITIES		5,357.1	5,312.7
Rate Matters
Commitments and Contingencies
Equity
Common Stock		135.7	135.7
Paid-in Capital		676.6	676.6
Retained Earnings		1,517.5	1,508.4
Accumulated Other Comprehensive Income (Loss)		(5.3)	(5.4)
TOTAL COMMON SHAREHOLDER'S EQUITY		2,324.5	2,315.3
Noncontrolling Interests		0.4	0.3
TOTAL EQUITY		2,324.9	2,315.6
TOTAL LIABILITIES AND EQUITY		$ 7,682	$ 7,628.3
[1]	Amount of securitized debt for receivables as accounted for under the “Transfers and Servicing” accounting guidance.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current Assets
Cash and Cash Equivalents	$ 227.7	$ 234.1
Restricted Cash	135.4	210
Other Temporary Investments	168.9	159.1
Fuel	360.3	341.5
Property, Plant and Equipment
Other Property, Plant and Equipment	4,202.7	4,265
Accumulated Depreciation and Amortization	18,182.6	17,986.1
Assets, Noncurrent [Abstract]
Securitized Assets	853	920.6
Current Liabilities
Long-term Debt Due Within One Year	1,528.5	1,698.5
Accrued Interest	306	231.7
Noncurrent Liabilities
Long-term Debt	$ 22,898.2	$ 21,648.2
Equity
Common Stock, Par Value Per Share	$ 6.50	$ 6.50
Common Stock, Shares Authorized	600,000,000	600,000,000
Common Stock, Shares, Issued	513,632,124	513,450,036
Treasury Stock, Shares	20,204,160	20,204,160
AEP Subsidiaries [Member]
Current Assets
Restricted Cash	$ 135.4	$ 210
Other Temporary Investments	159.1	152.7
Current Liabilities
Long-term Debt Due Within One Year	375.9	406.5
Noncurrent Liabilities
Long-term Debt	980	1,109.2
AEP Texas Inc. [Member]
Current Assets
Cash and Cash Equivalents	0.1	3.1
Restricted Cash	100.6	156.7
Fuel	8.5	8.8
Property, Plant and Equipment
Other Property, Plant and Equipment	734.5	727.9
Accumulated Depreciation and Amortization	1,686.6	1,651.2
Assets, Noncurrent [Abstract]
Securitized Assets	592.9	649.1
Current Liabilities
Long-term Debt Due Within One Year	508.6	501.1
Accrued Interest	50.7	37.3
Noncurrent Liabilities
Long-term Debt	3,269.7	3,380.2
AEP Texas Inc. [Member] | AEP Texas Central Transition Funding Co [Member]
Assets, Noncurrent [Abstract]
Securitized Assets	582.8	636.8
Current Liabilities
Long-term Debt Due Within One Year	258.6	251.1
Accrued Interest	7.4	11.3
Noncurrent Liabilities
Long-term Debt	429.4	540.1
AEP Transmission Co [Member]
Current Assets
Cash and Cash Equivalents	0	0
Property, Plant and Equipment
Other Property, Plant and Equipment	174.4	174
Accumulated Depreciation and Amortization	306.7	271.9
Current Liabilities
Long-term Debt Due Within One Year	85	85
Accrued Interest	35.1	15.9
Noncurrent Liabilities
Long-term Debt	2,738.4	2,738
Appalachian Power Co [Member]
Current Assets
Cash and Cash Equivalents	2.9	4.2
Restricted Cash	18.3	25.6
Fuel	69.9	61.3
Property, Plant and Equipment
Other Property, Plant and Equipment	504.5	485.8
Accumulated Depreciation and Amortization	4,174.9	4,124.4
Assets, Noncurrent [Abstract]
Securitized Assets	252.7	258.7
Current Liabilities
Long-term Debt Due Within One Year	345	430.7
Accrued Interest	74.2	41.5
Noncurrent Liabilities
Long-term Debt	$ 4,099	$ 3,631.9
Equity
Common Stock, Shares Authorized	30,000,000	30,000,000
Common Stock, Shares Outstanding	13,499,500	13,499,500
Indiana Michigan Power Co [Member]
Current Assets
Cash and Cash Equivalents	$ 1.7	$ 2.4
Fuel	32	37.3
Property, Plant and Equipment
Other Property, Plant and Equipment	580.1	583.8
Accumulated Depreciation and Amortization	3,208.4	3,151.6
Current Liabilities
Long-term Debt Due Within One Year	140.4	155.4
Accrued Interest	20.9	37.3
Noncurrent Liabilities
Long-term Debt	$ 2,871	$ 2,880
Equity
Common Stock, No Par Value	$ 0	$ 0
Common Stock, Shares Authorized	2,500,000	2,500,000
Common Stock, Shares Outstanding	1,400,000	1,400,000
Indiana Michigan Power Co [Member] | DCC Fuel [Member]
Current Liabilities
Long-term Debt Due Within One Year	$ 61.8	$ 76.8
Ohio Power Co [Member]
Current Assets
Cash and Cash Equivalents	3.3	4.9
Restricted Cash	16.5	27.6
Property, Plant and Equipment
Other Property, Plant and Equipment	580	574.8
Accumulated Depreciation and Amortization	2,224.1	2,218.6
Assets, Noncurrent [Abstract]
Securitized Assets	7.3	12.9
Current Liabilities
Long-term Debt Due Within One Year	24.6	47.9
Noncurrent Liabilities
Long-term Debt	$ 1,669	$ 1,668.7
Equity
Common Stock, No Par Value	$ 0	$ 0
Common Stock, Shares Authorized	40,000,000	40,000,000
Common Stock, Shares Outstanding	27,952,473	27,952,473
Ohio Power Co [Member] | Ohio Phase-In-Recovery Funding [Member]
Current Liabilities
Long-term Debt Due Within One Year	$ 24.5	$ 47.8
Public Service Co Of Oklahoma [Member]
Current Assets
Cash and Cash Equivalents	1.5	2
Fuel	10	12.3
Property, Plant and Equipment
Other Property, Plant and Equipment	306	303.5
Accumulated Depreciation and Amortization	1,496.2	1,472.9
Current Liabilities
Long-term Debt Due Within One Year	375.5	375.5
Noncurrent Liabilities
Long-term Debt	$ 1,010.7	$ 911.5
Equity
Common Stock, Par Value Per Share	$ 15	$ 15
Common Stock, Shares Authorized	11,000,000	11,000,000
Common Stock, Shares, Issued	10,482,000	10,482,000
Common Stock, Shares Outstanding	9,013,000	9,013,000
Southwestern Electric Power Co [Member]
Current Assets
Cash and Cash Equivalents	$ 22.1	$ 24.5
Fuel	135.1	120.5
Property, Plant and Equipment
Other Property, Plant and Equipment	658.9	762.7
Accumulated Depreciation and Amortization	2,760.6	2,808.3
Current Liabilities
Long-term Debt Due Within One Year	6.2	59.7
Accrued Interest	22	34.7
Noncurrent Liabilities
Long-term Debt	$ 2,652.9	$ 2,653.7
Equity
Common Stock, Par Value Per Share	$ 18	$ 18
Common Stock, Shares Authorized	7,600,000	7,600,000
Common Stock, Shares Outstanding	7,536,640	7,536,640
Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
Current Assets
Cash and Cash Equivalents	$ 20.2	$ 22
Fuel	31.4	35.7
Property, Plant and Equipment
Other Property, Plant and Equipment	210	276.9
Accumulated Depreciation and Amortization	$ 99.3	$ 174.6

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019		Mar. 31, 2018
Operating Activities
Net Income (Loss)	$ 574.1		$ 456.7
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	605.8		539.7
Deferred Income Taxes	16.8		87.3
Allowance for Equity Funds Used During Construction	(28.9)		(30.7)
Mark-to-Market of Risk Management Contracts	65.5		(0.7)
Amortization of Nuclear Fuel	25.1		27.4
Property Taxes	(75.6)		(63.7)
Deferred Fuel Over/Under-Recovery, Net	32.5		(61.2)
Recovery of Ohio Capacity Costs	14.7		18
Provision for Refund - Global Settlement	(4.1)		(5.4)
Change in Other Noncurrent Assets	(47.9)		(59.8)
Change in Other Noncurrent Liabilities	67.3		133.3
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	57.5		39.7
Fuel, Materials and Supplies	(26.4)		28.5
Accounts Payable	(152.6)		(129.3)
Accrued Taxes, Net	(77)		(74.3)
Other Current Assets	(18.8)		(40.1)
Other Current Liabilities	(219.7)		(63.2)
Net Cash Flows from (Used for) Operating Activities	808.3		802.2
Investing Activities
Construction Expenditures	(1,565.4)		(1,905.8)
Purchases of Investment Securities	(130.4)		(525.9)
Sales of Investment Securities	111.9		508.6
Acquisitions of Nuclear Fuel	(32.4)		(23.8)
Other Investing Activities	33.5		19.1
Net Cash Flows from (Used for) Investing Activities	(1,582.8)		(1,927.8)
Financing Activities
Issuance of Common Stock, Net	14.5		32.2
Issuance of Long-term Debt	1,285.6		841
Commercial Paper and Credit Facility Borrowings	0		205.6
Change in Short-term Debt, Net	(52)		814.6
Retirement of Long-term Debt	(220.6)		(544)
Principal Payments for Finance Lease Obligations	(14.3)		(16.8)
Dividends Paid on Common Stock	(333.6)		(306.1)
Other Financing Activities	13.9		3
Net Cash Flows from (Used for) Financing Activities	693.5		1,029.5
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(81)		(96.1)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	444.1		412.6
Cash and Cash Equivalents at Beginning of Period	234.1
Cash, Cash Equivalents and Restricted Cash at End of Period	363.1		316.5
Cash and Cash Equivalents at End of Period	227.7
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	168.9		188
Net Cash Paid (Received) for Income Taxes	(0.6)		(0.9)
Noncash Acquisitions Under Finance Leases	23.1		21.4
Construction Expenditures Included in Current Liabilities as of March 31,	846.3		799.9
Noncash Contribution of Assets by Noncontrolling Interest	0		84
Expected Reimbursement For Spent Nuclear Fuel Dry Cask Storage	1		0.1
Forward Equity Purchase Contract Included Current and Noncurrent Liabilities as of March 31,	(55.6)		16.9
AEP Texas Inc. [Member]
Operating Activities
Net Income (Loss)	34.4		46.8
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	138.9		110
Deferred Income Taxes	(11)		(4.4)
Allowance for Equity Funds Used During Construction	(1.8)		(5.5)
Mark-to-Market of Risk Management Contracts	0		0.2
Property Taxes	(73.8)		(56.1)
Change in Other Noncurrent Assets	(3.2)		(12.7)
Change in Other Noncurrent Liabilities	(5.7)		6.5
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(7.8)		1.8
Fuel, Materials and Supplies	(1)		(0.2)
Accounts Payable	4.2		(25.9)
Accrued Taxes, Net	57.5		25.2
Other Current Assets	0.5		(1.6)
Other Current Liabilities	(4.4)		(5.1)
Net Cash Flows from (Used for) Operating Activities	126.8		79
Investing Activities
Construction Expenditures	(343.1)		(481.6)
Change in Advances to Affiliates, Net	0.3		103.8
Other Investing Activities	6.2		13.4
Net Cash Flows from (Used for) Investing Activities	(336.6)		(364.4)
Financing Activities
Capital Contributions from Parent	200		100
Change in Advances from Affiliates, Net	55.2		232.7
Retirement of Long-term Debt	(103.5)		(96.5)
Principal Payments for Finance Lease Obligations	(1.2)		(1.1)
Other Financing Activities	0.2		0.3
Net Cash Flows from (Used for) Financing Activities	150.7		235.4
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(59.1)		(50)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	159.8		157.2
Cash and Cash Equivalents at Beginning of Period	3.1
Cash, Cash Equivalents and Restricted Cash at End of Period	100.7		107.2
Cash and Cash Equivalents at End of Period	0.1
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	22.4		27.8
Net Cash Paid (Received) for Income Taxes	(5.6)		0
Noncash Acquisitions Under Finance Leases	2.4		4
Construction Expenditures Included in Current Liabilities as of March 31,	195.7		169.3
AEP Transmission Co [Member]
Operating Activities
Net Income (Loss)	104.3		84.1	[1]
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	40.3		30.3
Deferred Income Taxes	14.5		15.5
Allowance for Equity Funds Used During Construction	(11.3)		(14.9)
Property Taxes	23.2		17.3
Change in Other Noncurrent Assets	2.7		2.9
Change in Other Noncurrent Liabilities	2.2		23.9
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(8.2)		(9.6)
Fuel, Materials and Supplies	(0.6)		(1.9)
Accounts Payable	11.4		(10.7)
Accrued Taxes, Net	(32.1)		(34)
Accrued Interest	19.2		23.3
Other Current Assets	0.4		0.3
Other Current Liabilities	0.2		0.6
Net Cash Flows from (Used for) Operating Activities	166.2		127.1
Investing Activities
Construction Expenditures	(365)		(571.8)
Change in Advances to Affiliates, Net	23.4		114.2
Payments to Acquire Property, Plant, and Equipment	(2.5)		(1.8)
Other Investing Activities	0.3		1
Net Cash Flows from (Used for) Investing Activities	(343.8)		(458.4)
Financing Activities
Capital Contributions from Parent	0		65
Change in Advances from Affiliates, Net	177.7		266.4
Other Financing Activities	(0.1)		(0.1)
Net Cash Flows from (Used for) Financing Activities	177.6		331.3
Net Increase (Decrease) in Cash and Cash Equivalents	0		0
Cash and Cash Equivalents at Beginning of Period	0		0
Cash and Cash Equivalents at End of Period	0		0
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	1.6		(3)
Net Cash Paid (Received) for Income Taxes	(1.2)		0
Construction Expenditures Included in Current Liabilities as of March 31,	261.1		213.8
Appalachian Power Co [Member]
Operating Activities
Net Income (Loss)	133.7		125.5
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	112.5		108.5
Deferred Income Taxes	(45)		11
Carrying Costs Income	0		(0.5)
Allowance for Equity Funds Used During Construction	(1.7)		(2.6)
Mark-to-Market of Risk Management Contracts	50.6		14.9
Deferred Fuel Over/Under-Recovery, Net	20.8		(90.7)
Change in Other Noncurrent Assets	(12.1)		3.9
Change in Other Noncurrent Liabilities	(20.5)		37.9
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	19.5		(14.2)
Fuel, Materials and Supplies	(9.6)		19.3
Accounts Payable	(8.3)		(21.6)
Accrued Taxes, Net	13.7		17.8
Other Current Assets	(0.8)		(15.8)
Other Current Liabilities	(2.3)		5.6
Net Cash Flows from (Used for) Operating Activities	250.5		199.5
Investing Activities
Construction Expenditures	(205.1)		(218.5)
Change in Advances to Affiliates, Net	(193.6)		0
Other Investing Activities	15.2		4.4
Net Cash Flows from (Used for) Investing Activities	(383.5)		(214.1)
Financing Activities
Issuance of Long-term Debt	393.3		0
Change in Advances from Affiliates, Net	(205.6)		59.9
Retirement of Long-term Debt	(12)		(11.7)
Principal Payments for Finance Lease Obligations	(1.6)		(1.7)
Dividends Paid on Common Stock	(50)		(40)
Other Financing Activities	0.3		0.2
Net Cash Flows from (Used for) Financing Activities	124.4		6.7
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(8.6)		(7.9)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	29.8		19.2
Cash and Cash Equivalents at Beginning of Period	4.2
Cash, Cash Equivalents and Restricted Cash at End of Period	21.2		11.3
Cash and Cash Equivalents at End of Period	2.9
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	14.5		23.4
Net Cash Paid (Received) for Income Taxes	8		0
Noncash Acquisitions Under Finance Leases	2.1		1.8
Construction Expenditures Included in Current Liabilities as of March 31,	87.8		94.5
Indiana Michigan Power Co [Member]
Operating Activities
Net Income (Loss)	98.9		64.2
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	86.2		59.3
Deferred Income Taxes	(13.9)		13.7
Deferral of Incremental Nuclear Refueling Outage Expenses, Net	(14.8)		(12.3)
Carrying Costs Income	0.7		(2.4)
Allowance for Equity Funds Used During Construction	(6.2)		(1.8)
Mark-to-Market of Risk Management Contracts	4.7		3.4
Amortization of Nuclear Fuel	25.1		27.4
Deferred Fuel Over/Under-Recovery, Net	(5.2)		3.4
Change in Other Noncurrent Assets	12.8		(11)
Change in Other Noncurrent Liabilities	5.2		33.7
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	16		3.5
Fuel, Materials and Supplies	6.6		(4.5)
Accounts Payable	(3.1)		1.3
Accrued Taxes, Net	25.6		8.2
Other Current Assets	1.4		(11.1)
Other Current Liabilities	(35.2)		(27.8)
Net Cash Flows from (Used for) Operating Activities	204.8		147.2
Investing Activities
Construction Expenditures	(149.3)		(148.9)
Change in Advances to Affiliates, Net	(0.1)		(0.1)
Purchases of Investment Securities	(130.3)		(525.3)
Sales of Investment Securities	111.9		508.6
Acquisitions of Nuclear Fuel	(32.4)		(23.8)
Other Investing Activities	8.6		4.2
Net Cash Flows from (Used for) Investing Activities	(191.6)		(185.3)
Financing Activities
Change in Advances from Affiliates, Net	33.6		102.5
Retirement of Long-term Debt	(26.5)		(29.4)
Principal Payments for Finance Lease Obligations	(1.2)		(2.7)
Dividends Paid on Common Stock	(20)		(33.5)
Other Financing Activities	0.2		0.5
Net Cash Flows from (Used for) Financing Activities	(13.9)		37.4
Net Increase (Decrease) in Cash and Cash Equivalents	(0.7)		(0.7)
Cash and Cash Equivalents at Beginning of Period	2.4		1.3
Cash and Cash Equivalents at End of Period	1.7		0.6
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	43.3		50.6
Net Cash Paid (Received) for Income Taxes	(3.3)		0
Noncash Acquisitions Under Finance Leases	1.7		1.7
Construction Expenditures Included in Current Liabilities as of March 31,	80		77.2
Acquisition of Nuclear Fuel Included in Current Liabilities as of March 31,	1		0.1
Expected Reimbursement For Spent Nuclear Fuel Dry Cask Storage	7.9		0.1
Ohio Power Co [Member]
Operating Activities
Net Income (Loss)	128		79.6
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	63.3		64.8
Amortization Of Generation Deferrals	32.4		58.6
Deferred Income Taxes	10.1		(4.9)
Carrying Costs Income	(0.2)		(0.7)
Allowance for Equity Funds Used During Construction	(5.2)		(2.5)
Mark-to-Market of Risk Management Contracts	6.7		(33.7)
Property Taxes	66		62.9
Provision for Refund - Global Settlement	(4.1)		(5.4)
Reversal of a Regulatory Provision	(56.2)		0
Change in Other Noncurrent Assets	(7.3)		14.3
Change in Other Noncurrent Liabilities	17.6		40.6
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	31.7		38.8
Fuel, Materials and Supplies	(3.4)		(1.9)
Accounts Payable	(23.9)		(22.5)
Accrued Taxes, Net	(114.4)		(92.8)
Other Current Assets	(7.7)		(7.5)
Other Current Liabilities	(16.2)		(2.9)
Net Cash Flows from (Used for) Operating Activities	117.2		184.8
Investing Activities
Construction Expenditures	(198.5)		(168.2)
Change in Advances to Affiliates, Net	0		(200.4)
Other Investing Activities	3.7		1.7
Net Cash Flows from (Used for) Investing Activities	(194.8)		(366.9)
Financing Activities
Issuance of Long-term Debt	0		393.3
Change in Advances from Affiliates, Net	113.5		(87.8)
Retirement of Long-term Debt	(23.4)		(22.9)
Principal Payments for Finance Lease Obligations	(0.7)		(0.9)
Dividends Paid on Common Stock	(25)		(112.5)
Other Financing Activities	0.5		0.5
Net Cash Flows from (Used for) Financing Activities	64.9		169.7
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(12.7)		(12.4)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	32.5		29.7
Cash and Cash Equivalents at Beginning of Period	4.9
Cash, Cash Equivalents and Restricted Cash at End of Period	19.8		17.3
Cash and Cash Equivalents at End of Period	3.3
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	17		17
Net Cash Paid (Received) for Income Taxes	(0.2)		0
Noncash Acquisitions Under Finance Leases	3.2		1.4
Construction Expenditures Included in Current Liabilities as of March 31,	72.8		52.3
Public Service Co Of Oklahoma [Member]
Operating Activities
Net Income (Loss)	6.2		(7.2)
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	43.5		36.8
Deferred Income Taxes	(5.8)		(4.5)
Allowance for Equity Funds Used During Construction	(0.1)		0.1
Mark-to-Market of Risk Management Contracts	5.1		3.5
Property Taxes	(29.9)		(30.1)
Deferred Fuel Over/Under-Recovery, Net	(2.4)		14.6
Change in Other Noncurrent Assets	8		0
Change in Other Noncurrent Liabilities	(0.7)		5.7
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	2		6.9
Fuel, Materials and Supplies	3.2		(1.7)
Accounts Payable	(23.3)		(10.9)
Accrued Taxes, Net	25.3		22.4
Other Current Assets	(3.8)		0.9
Other Current Liabilities	4.4		(1.3)
Net Cash Flows from (Used for) Operating Activities	31.7		35.2
Investing Activities
Construction Expenditures	(70.7)		(54.4)
Other Investing Activities	0.4		2
Net Cash Flows from (Used for) Investing Activities	(70.3)		(52.4)
Financing Activities
Issuance of Long-term Debt	99.9		0
Change in Advances from Affiliates, Net	(50.3)		29.5
Retirement of Long-term Debt	(0.1)		(0.1)
Principal Payments for Finance Lease Obligations	(0.7)		(1)
Dividends Paid on Common Stock	(11.3)		(12.5)
Other Financing Activities	0.6		0.3
Net Cash Flows from (Used for) Financing Activities	38.1		16.2
Net Increase (Decrease) in Cash and Cash Equivalents	(0.5)		(1)
Cash and Cash Equivalents at Beginning of Period	2		1.6
Cash and Cash Equivalents at End of Period	1.5		0.6
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	10.9		10.3
Net Cash Paid (Received) for Income Taxes	0.6		0
Noncash Acquisitions Under Finance Leases	1.1		0.9
Construction Expenditures Included in Current Liabilities as of March 31,	15.6		25.4
Southwestern Electric Power Co [Member]
Operating Activities
Net Income (Loss)	29		13.4
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	62.1		57.4
Deferred Income Taxes	(2.5)		1
Allowance for Equity Funds Used During Construction	(1.8)		(2.3)
Mark-to-Market of Risk Management Contracts	2.3		5.1
Property Taxes	(48.9)		(48.8)
Deferred Fuel Over/Under-Recovery, Net	10.3		(4.6)
Change in Other Noncurrent Assets	2.9		1.3
Change in Other Noncurrent Liabilities	7.9		18.8
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	6.3		27.9
Fuel, Materials and Supplies	(16.2)		2.2
Accounts Payable	(55)		(24.6)
Accrued Taxes, Net	52.7		55.2
Accrued Interest	(12.7)		(13)
Other Current Assets	(10)		(0.8)
Other Current Liabilities	(17)		(12.5)
Net Cash Flows from (Used for) Operating Activities	9.4		75.7
Investing Activities
Construction Expenditures	(86.6)		(139.7)
Change in Advances to Affiliates, Net	81.4		0
Other Investing Activities	(3.1)		(5.4)
Net Cash Flows from (Used for) Investing Activities	(8.3)		(145.1)
Financing Activities
Issuance of Long-term Debt	0		444.6
Change in Short-term Debt, Net	0		0.6
Change in Advances from Affiliates, Net	74		29.9
Retirement of Long-term Debt	(55.1)		(383.4)
Principal Payments for Finance Lease Obligations	(2.7)		(2.8)
Dividends Paid on Common Stock	(18.7)		(20)
Dividends Paid on Common Stock	(1.1)		(0.8)
Other Financing Activities	0.1		0.4
Net Cash Flows from (Used for) Financing Activities	(3.5)		68.5
Net Increase (Decrease) in Cash and Cash Equivalents	(2.4)		(0.9)
Cash and Cash Equivalents at Beginning of Period	24.5		1.6
Cash and Cash Equivalents at End of Period	22.1		0.7
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	40.5		43.7
Net Cash Paid (Received) for Income Taxes	0.2		(0.1)
Noncash Acquisitions Under Finance Leases	0.8		1.9
Construction Expenditures Included in Current Liabilities as of March 31,	44.8		50.3
Additional Paid-in Capital [Member]
Supplementary Information
Forward Equity Purchase Contract Included Current and Noncurrent Liabilities as of March 31,	$ 62.1	[2]	$ 0
[1]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[2]	Includes $(62) million related to a forward equity purchase contract associated with the issuance of Equity Units. See “Equity Units” section of Footnote 13

Significant Accounting Matters

Significant Accounting Matters	3 Months Ended
	Mar. 31, 2019
Significant Accounting Matters	SIGNIFICANT ACCOUNTING MATTERS The disclosures in this note apply to all Registrants unless indicated otherwise. General The unaudited condensed financial statements and footnotes were prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the SEC. Accordingly, they do not include all of the information and footnotes required by GAAP for complete annual financial statements. In the opinion of management, the unaudited condensed interim financial statements reflect all normal and recurring accruals and adjustments necessary for a fair presentation of the net income, financial position and cash flows for the interim periods for each Registrant. Net income for the three months ended March 31, 2019 is not necessarily indicative of results that may be expected for the year ending December 31, 2019 . The condensed financial statements are unaudited and should be read in conjunction with the audited 2018 financial statements and notes thereto, which are included in the Registrants’ Annual Reports on Form 10-K as filed with the SEC on February 21, 2019 . Earnings Per Share (EPS) (Applies to AEP) Basic EPS is calculated by dividing net earnings available to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted EPS is calculated by adjusting the weighted-average outstanding common shares, assuming conversion of all potentially dilutive stock options and awards. The following table presents AEP’s basic and diluted EPS calculations included on the statements of income: Three Months Ended March 31, 2019 2018 (in millions, except per share data) $/share $/share Earnings Attributable to AEP Common Shareholders $ 572.8 $ 454.4 Weighted Average Number of Basic Shares Outstanding 493.3 $ 1.16 492.3 $ 0.92 Weighted Average Dilutive Effect of Stock-Based Awards 1.2 — 0.8 — Weighted Average Number of Diluted Shares Outstanding 494.5 $ 1.16 493.1 $ 0.92 Equity Units issued in March 2019 are potentially dilutive securities but were excluded from the calculation of diluted EPS for the three months ended March 31, 2019 , as the dilutive stock price threshold was not met. See Note 13 - Financing Activities for more information related to Equity Units. There were no antidilutive shares outstanding as of March 31, 2019 and 2018 . Restricted Cash (Applies to AEP, AEP Texas, APCo and OPCo) Restricted Cash primarily includes funds held by trustees for the payment of securitization bonds. Reconciliation of Cash, Cash Equivalents and Restricted Cash The following tables provide a reconciliation of Cash, Cash Equivalents and Restricted Cash reported within the balance sheet that sum to the total of the same amounts shown on the statement of cash flows: March 31, 2019 AEP AEP Texas APCo OPCo (in millions) Cash and Cash Equivalents $ 227.7 $ 0.1 $ 2.9 $ 3.3 Restricted Cash 135.4 100.6 18.3 16.5 Total Cash, Cash Equivalents and Restricted Cash $ 363.1 $ 100.7 $ 21.2 $ 19.8 December 31, 2018 AEP AEP Texas APCo OPCo (in millions) Cash and Cash Equivalents $ 234.1 $ 3.1 $ 4.2 $ 4.9 Restricted Cash 210.0 156.7 25.6 27.6 Total Cash, Cash Equivalents and Restricted Cash $ 444.1 $ 159.8 $ 29.8 $ 32.5 Revisions to Previously Issued Financial Statements (Applies to AEPTCo) In the second quarter of 2018, management identified certain transmission assets that it believes should not have been included in AEPTCo’s SPP transmission formula rates. As a result, AEPTCo recorded a pretax out of period correction of an error of approximately $17 million related to revenue recorded from 2013 through March 31, 2018 in the second quarter of 2018 . Subsequent to filing the second quarter 2018 Form 10-Q, AEPTCo identified an additional error in its previously issued financial statements. This error resulted from the improper capitalization of AFUDC and subsequent revenue recorded on the AFUDC. The impact of this misstatement reduced AEPTCo’s pretax income by approximately $7 million on a cumulative basis for the period 2011 through June 30, 2018 . Management assessed the materiality of the misstatements on all previously issued AEPTCo financial statements in accordance with SEC Staff Accounting Bulletin (SAB) No. 99, Materiality, codified in ASC 250, Presentation of Financial Statements and concluded these misstatements were not material, individually or in the aggregate, to any prior annual or interim period. In accordance with ASC 250 (SAB No. 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements), management revised the prior period AEPTCo financial statements included in this report to reflect the impact of correcting the immaterial misstatements described above. In addition, management will revise the June 30, 2018 period presented in AEPTCo’s previously issued financial statements in the quarterly period ended June 30, 2019 SEC Form 10-Q filing to reflect the impact of the misstatements. AEPTCo has also corrected other immaterial out of period adjustments. The impact of these additional adjustments did not impact net income in any period. Management also assessed the materiality of AEPTCo’s misstatements discussed above on all previously issued AEP financial statements in accordance with ASC 250, and concluded these misstatements were not material, individually or in the aggregate, to any prior interim and annual period financial statements. As a result, AEP recorded the correction in the third quarter of 2018. Statement of Income The table below reflects the effects of correcting the immaterial errors described above on AEPTCo’s statement of income for the three months ended March 31, 2018: Three Months Ended March 31, 2018 As Reported Adjustments As Adjusted (in millions) TOTAL REVENUES $ 193.5 $ (1.8 ) $ 191.7 EXPENSES Depreciation and Amortization 30.6 (0.3 ) 30.3 TOTAL EXPENSES 80.9 (0.3 ) 80.6 OPERATING INCOME 112.6 (1.5 ) 111.1 Other Income (Expense): Allowance for Equity Funds Used During Construction 15.3 (0.4 ) 14.9 Interest Expense (19.9 ) (0.4 ) (20.3 ) INCOME BEFORE INCOME TAX EXPENSE 108.4 (2.3 ) 106.1 Income Tax Expense 22.5 (0.5 ) 22.0 NET INCOME $ 85.9 $ (1.8 ) $ 84.1 Statement of Cash Flows The table below reflects the effects of correcting the immaterial errors described above on AEPTCo’s statement of cash flows for the three months ended March 31, 2018: Three Months Ended March 31, 2018 As Reported Adjustments As Adjusted (in millions) OPERATING ACTIVITIES Net Income $ 85.9 $ (1.8 ) $ 84.1 Adjustments to Reconcile Net Income to Net Cash Flows from Operating Activities: Depreciation and Amortization 30.6 (0.3 ) 30.3 Deferred Income Taxes 15.7 (0.2 ) 15.5 Allowance for Equity Funds Used During Construction (15.3 ) 0.4 (14.9 ) Change in Other Noncurrent Assets 2.7 0.2 2.9 Changes in Certain Components of Working Capital: Accounts Receivable, Net (10.1 ) 0.5 (9.6 ) Accounts Payable (12.3 ) 1.6 (10.7 ) Accrued Taxes, Net (33.6 ) (0.4 ) (34.0 ) Net Cash Flows from Operating Activities 127.1 — 127.1 INVESTING ACTIVITIES Net Cash Flows Used for Investing Activities (458.4 ) — (458.4 ) FINANCING ACTIVITIES Net Cash Flows from Financing Activities 331.3 — 331.3 Net Change in Cash and Cash Equivalents — — — Cash and Cash Equivalents at Beginning of Period — — — Cash and Cash Equivalents at End of Period $ — $ — $ — SUPPLEMENTARY INFORMATION Construction Expenditures Included in Current Liabilities as of March 31, $ 210.6 $ 3.2 $ 213.8 Statement of Changes in Member’s Equity The statement of changes in AEPTCo’s member’s equity reflects the adjustments to Net Income of $(2) million for the three months ended March 31, 2018 as shown in the table under Net Income above. The statement of changes in member’s equity also reflects the adjustments to Retained Earnings of $(15) million

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements	NEW ACCOUNTING PRONOUNCEMENTS The disclosures in this note apply to all Registrants unless indicated otherwise. During FASB’s standard-setting process and upon issuance of final pronouncements, management reviews the new accounting literature to determine its relevance, if any, to the Registrants’ business. The following pronouncements will impact the financial statements. ASU 2016-02 “Accounting for Leases” (ASU 2016-02) In February 2016, the FASB issued ASU 2016-02 increasing the transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheets and disclosing key information about leasing arrangements. Under the new standard, an entity must recognize an asset and liability for operating leases on the balance sheets. Additionally, a capital lease will be known as a finance lease going forward. Leases with terms of 12 months or longer will be subject to the new requirements. Fundamentally, the criteria used to determine lease classification will remain the same, but will be more subjective under the new standard. New leasing standard implementation activities included the identification of the lease population within the AEP System as well as the sampling of representative lease contracts to analyze accounting treatment under the new accounting guidance. Based upon the completed assessments, management also prepared a gap analysis to outline new disclosure compliance requirements. Management adopted ASU 2016-02 effective January 1, 2019 by means of a cumulative-effect adjustment to the balance sheet. Management elected the following practical expedients upon adoption: Practical Expedient Description Overall Expedients (for leases commenced prior to adoption date and must be adopted as a package) Do not need to reassess whether any expired or existing contracts are/or contain leases, do not need to reassess the lease classification for any expired or existing leases and do not need to reassess initial direct costs for any existing leases. Lease and Non-lease Components (elect by class of underlying asset) Elect as an accounting policy to not separate non-lease components from lease components and instead account for each lease and associated non-lease component as a single lease component. Short-term Lease (elect by class of underlying asset) Elect as an accounting policy to not apply the recognition requirements to short-term leases. Existing and expired land easements not previously accounted for as leases Elect optional transition practical expedient to not evaluate under Topic 842 existing or expired land easements that were not previously accounted for as leases under the current leases guidance in Topic 840. Cumulative-effect adjustment in the period of adoption Elect the optional transition practical expedient to adopt the new lease requirements through a cumulative-effect adjustment on the balance sheet in the period of adoption. Management concluded that the result of adoption would not materially change the volume of contracts that qualify as leases going forward. The adoption of the new standard did not materially impact results of operations or cash flows, but did have a material impact on the balance sheet. See Note 12 - Leases for additional disclosures required by the new standard. ASU 2016-13 “Measurement of Credit Losses on Financial Instruments” (ASU 2016-13) In June 2016, the FASB issued ASU 2016-13 requiring an allowance to be recorded for all expected credit losses for financial assets. The allowance for credit losses is based on historical information, current conditions and reasonable and supportable forecasts. The new standard also makes revisions to the other-than-temporary impairment model for available-for-sale debt securities. Disclosures of credit quality indicators in relation to the amortized cost of financing receivables are further disaggregated by year of origination. The new accounting guidance is effective for interim and annual periods beginning after December 15, 2019, with early adoption permitted for interim and annual periods beginning after December 15, 2018. The amendments will be applied through a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. Management is analyzing the impact of this new standard and, at this time, cannot estimate the impact of adoption on net income. Management plans to adopt ASU 2016-13 and related implementation guidance effective January 1, 2020. ASU 2018-15 “Internal-Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract” (ASU 2018-15) In August 2018, the FASB issued ASU 2018-15 aligning the requirements for capitalizing implementation costs incurred in a cloud computing arrangement (hosting arrangement) that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The new standard requires an entity (customer) in a hosting arrangement that is a service contract to follow the accounting guidance for “Internal-Use Software” to determine which implementation costs to capitalize as an asset related to the service contract and which costs to expense. To eliminate diversity in practice, the new standard changes the presentation of implementation costs for cloud service arrangements that are service contracts without the purchase of a license. Implementation costs for cloud service contracts will be presented on the balance sheets in the same manner as a prepayment. The Registrants currently present implementation costs in property, plant and equipment on the balance sheets. Under the new standard, amortization of capitalized implementation costs of a hosting arrangement will be recorded in Operation and Maintenance expense over the term of the cloud service arrangement, rather than Depreciation and Amortization expense on the statements of income. Payments for capitalized implementation costs in the statement of cash flows will be classified in the same manner as payments made for fees associated with the hosting element.

Comprehensive Income

Comprehensive Income	3 Months Ended
	Mar. 31, 2019
Comprehensive Income	COMPREHENSIVE INCOME The disclosures in this note apply to all Registrants except for AEPTCo. AEPTCo does not have any components of other comprehensive income for any period presented in the financial statements. Presentation of Comprehensive Income The following tables provide the components of changes in AOCI and details of reclassifications from AOCI for the three months ended March 31, 2019 and 2018 . The amortization of pension and OPEB AOCI components are included in the computation of net periodic pension and OPEB costs. See Note 7 - Benefit Plans for additional details. AEP Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedges Commodity Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (23.0 ) $ (12.6 ) $ (84.8 ) $ (120.4 ) Change in Fair Value Recognized in AOCI (38.8 ) — — (38.8 ) Amount of (Gain) Loss Reclassified from AOCI Purchased Electricity for Resale (a) 12.3 — — 12.3 Interest Expense (a) — 0.2 — 0.2 Amortization of Prior Service Cost (Credit) — — (4.8 ) (4.8 ) Amortization of Actuarial (Gains) Losses — — 3.0 3.0 Reclassifications from AOCI, before Income Tax (Expense) Benefit 12.3 0.2 (1.8 ) 10.7 Income Tax (Expense) Benefit 2.6 — (0.4 ) 2.2 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 9.7 0.2 (1.4 ) 8.5 Net Current Period Other Comprehensive Income (Loss) (29.1 ) 0.2 (1.4 ) (30.3 ) Balance in AOCI as of March 31, 2019 $ (52.1 ) $ (12.4 ) $ (86.2 ) $ (150.7 ) AEP Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedges Commodity Interest Rate Securities Available for Sale Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (28.4 ) $ (13.0 ) $ 11.9 $ (38.3 ) $ (67.8 ) Change in Fair Value Recognized in AOCI 12.8 — — — 12.8 Amount of (Gain) Loss Reclassified from AOCI Purchased Electricity for Resale (a) (13.1 ) — — — (13.1 ) Interest Expense (a) — 0.3 — — 0.3 Amortization of Prior Service Cost (Credit) — — — (5.0 ) (5.0 ) Amortization of Actuarial (Gains) Losses — — — 3.2 3.2 Reclassifications from AOCI, before Income Tax (Expense) Benefit (13.1 ) 0.3 — (1.8 ) (14.6 ) Income Tax (Expense) Benefit (2.8 ) 0.1 — (0.4 ) (3.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (10.3 ) 0.2 — (1.4 ) (11.5 ) Net Current Period Other Comprehensive Income (Loss) 2.5 0.2 — (1.4 ) 1.3 ASU 2018-02 Adoption (6.1 ) (2.7 ) — (8.2 ) (17.0 ) ASU 2016-01 Adoption — — (11.9 ) — (11.9 ) Balance in AOCI as of March 31, 2018 $ (32.0 ) $ (15.5 ) $ — $ (47.9 ) $ (95.4 ) AEP Texas Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (4.4 ) $ (10.7 ) $ (15.1 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.4 — 0.4 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.4 — 0.4 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.3 — 0.3 Net Current Period Other Comprehensive Income (Loss) 0.3 — 0.3 Balance in AOCI as of March 31, 2019 $ (4.1 ) $ (10.7 ) $ (14.8 ) AEP Texas Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (4.5 ) $ (8.1 ) $ (12.6 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.3 — 0.3 Amortization of Actuarial (Gains) Losses — 0.1 0.1 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.3 0.1 0.4 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.2 0.1 0.3 Net Current Period Other Comprehensive Income (Loss) 0.2 0.1 0.3 ASU 2018-02 Adoption (0.9 ) (1.8 ) (2.7 ) Balance in AOCI as of March 31, 2018 $ (5.2 ) $ (9.8 ) $ (15.0 ) APCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ 1.8 $ (6.8 ) $ (5.0 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.3 ) — (0.3 ) Amortization of Prior Service Cost (Credit) — (1.3 ) (1.3 ) Amortization of Actuarial (Gains) Losses — 0.5 0.5 Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.3 ) (0.8 ) (1.1 ) Income Tax (Expense) Benefit (0.1 ) (0.2 ) (0.3 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.2 ) (0.6 ) (0.8 ) Net Current Period Other Comprehensive Income (Loss) (0.2 ) (0.6 ) (0.8 ) Balance in AOCI as of March 31, 2019 $ 1.6 $ (7.4 ) $ (5.8 ) APCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedges Commodity Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ — $ 2.2 $ (0.9 ) $ 1.3 Change in Fair Value Recognized in AOCI (0.7 ) — — (0.7 ) Amount of (Gain) Loss Reclassified from AOCI Purchased Electricity for Resale (a) 0.9 — — 0.9 Interest Expense (a) — (0.3 ) — (0.3 ) Amortization of Prior Service Cost (Credit) — — (1.3 ) (1.3 ) Amortization of Actuarial (Gains) Losses — — 0.3 0.3 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.9 (0.3 ) (1.0 ) (0.4 ) Income Tax (Expense) Benefit 0.2 (0.1 ) (0.2 ) (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.7 (0.2 ) (0.8 ) (0.3 ) Net Current Period Other Comprehensive Income (Loss) — (0.2 ) (0.8 ) (1.0 ) ASU 2018-02 Adoption — 0.5 (0.2 ) 0.3 Balance in AOCI as of March 31, 2018 $ — $ 2.5 $ (1.9 ) $ 0.6 I&M Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (11.5 ) $ (2.3 ) $ (13.8 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.2 ) (0.2 ) Amortization of Actuarial (Gains) Losses — 0.2 0.2 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 — 0.5 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 — 0.4 Net Current Period Other Comprehensive Income (Loss) 0.4 — 0.4 Balance in AOCI as of March 31, 2019 $ (11.1 ) $ (2.3 ) $ (13.4 ) I&M Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (10.7 ) $ (1.4 ) $ (12.1 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.2 ) (0.2 ) Amortization of Actuarial (Gains) Losses — 0.2 0.2 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 — 0.5 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 — 0.4 Net Current Period Other Comprehensive Income (Loss) 0.4 — 0.4 ASU 2018-02 Adoption (2.4 ) (0.3 ) (2.7 ) Balance in AOCI as of March 31, 2018 $ (12.7 ) $ (1.7 ) $ (14.4 ) OPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2018 $ 1.0 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.4 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.4 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.3 ) Net Current Period Other Comprehensive Income (Loss) (0.3 ) Balance in AOCI as of March 31, 2019 $ 0.7 OPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2017 $ 1.9 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.4 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.4 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.3 ) Net Current Period Other Comprehensive Income (Loss) (0.3 ) ASU 2018-02 Adoption 0.4 Balance in AOCI as of March 31, 2018 $ 2.0 PSO Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2018 $ 2.1 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.3 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.3 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.2 ) Net Current Period Other Comprehensive Income (Loss) (0.2 ) Balance in AOCI as of March 31, 2019 $ 1.9 PSO Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2017 $ 2.6 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.3 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.3 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.2 ) Net Current Period Other Comprehensive Income (Loss) (0.2 ) ASU 2018-02 Adoption 0.5 Balance in AOCI as of March 31, 2018 $ 2.9 SWEPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (3.3 ) $ (2.1 ) $ (5.4 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.5 ) (0.5 ) Amortization of Actuarial (Gains) Losses — 0.1 0.1 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 (0.4 ) 0.1 Income Tax (Expense) Benefit 0.1 (0.1 ) — Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 (0.3 ) 0.1 Net Current Period Other Comprehensive Income (Loss) 0.4 (0.3 ) 0.1 Balance in AOCI as of March 31, 2019 $ (2.9 ) $ (2.4 ) $ (5.3 ) SWEPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (6.0 ) $ 2.0 $ (4.0 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.5 ) (0.5 ) Amortization of Actuarial (Gains) Losses — 0.1 0.1 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 (0.4 ) 0.1 Income Tax (Expense) Benefit 0.1 (0.1 ) — Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 (0.3 ) 0.1 Net Current Period Other Comprehensive Income (Loss) 0.4 (0.3 ) 0.1 ASU 2018-02 Adoption (1.3 ) 0.4 (0.9 ) Balance in AOCI as of March 31, 2018 $ (6.9 ) $ 2.1 $ (4.8 ) (a)

Rate Matters

Rate Matters	3 Months Ended
	Mar. 31, 2019
Rate Matters	RATE MATTERS The disclosures in this note apply to all Registrants unless indicated otherwise. As discussed in the 2018 Annual Report, the Registrants are involved in rate and regulatory proceedings at the FERC and their state commissions. The Rate Matters note within the 2018 Annual Report should be read in conjunction with this report to gain a complete understanding of material rate matters still pending that could impact net income, cash flows and possibly financial condition. The following discusses rate-making developments in 2019 and updates the 2018 Annual Report. Regulated Generating Unit to be Retired by 2020 (Applies to AEP and PSO) In September 2018, management announced that the Oklaunion Power Station is probable of abandonment and is to be retired by October 2020. The table below summarizes the plant investment and cost of removal, currently being recovered, as well as the regulatory asset for accelerated depreciation for the generating unit as of March 31, 2019 . See “2018 Oklahoma Base Rate Case” below for additional information. Gross Investment Accumulated Depreciation Net Investment Accelerated Depreciation Regulatory Asset (a) Materials and Supplies Cost of Removal Regulatory Liability Expected Retirement Date Remaining Recovery Period (dollars in millions) $ 106.5 $ 68.7 $ 37.8 $ 10.9 $ 3.1 $ 5.0 2020 27 years (a) In October 2018, PSO changed depreciation rates to utilize the 2020 end-of-life and defer depreciation expense to a regulatory asset for the amount in excess of the previously OCC-approved depreciation rates for Oklaunion Power Station. See “2018 Oklahoma Base Rate Case” discussion below for additional information. Regulatory Assets Pending Final Regulatory Approval (Applies to all Registrants except AEPTCo) AEP March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Plant Retirement Costs - Unrecovered Plant $ 50.3 $ 50.3 Kentucky Deferred Purchase Power Expenses 18.4 14.5 Other Regulatory Assets Pending Final Regulatory Approval 16.4 14.8 Regulatory Assets Currently Not Earning a Return Storm Related Costs (a) 152.0 152.4 Plant Retirement Costs - Asset Retirement Obligation Costs 35.3 35.3 Other Regulatory Assets Pending Final Regulatory Approval 15.4 20.7 Total Regulatory Assets Pending Final Regulatory Approval (b) $ 287.8 $ 288.0 (a) As of March 31, 2019 , AEP Texas has deferred $137 million related to Hurricane Harvey. In March 2019, AEP Texas filed a request to securitize total estimated distribution-related system restoration costs with the PUCT. See “Texas Storm Cost Securitization” discussion below for additional information. (b) In 2015, APCo recorded a $91 million reduction to accumulated depreciation related to the remaining net book value of plants retired in 2015, primarily in its Virginia jurisdiction. These plants were normal retirements at the end of their depreciable lives under the group composite method of depreciation. APCo’s recovery of the remaining Virginia net book value for the retired plants will be considered in the Virginia SCC’s 2020 triennial review of APCo’s generation and distribution base rates. AEP Texas March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Not Earning a Return Storm-Related Costs (a) $ 152.0 $ 152.4 Rate Case Expense 0.4 0.2 Total Regulatory Assets Pending Final Regulatory Approval $ 152.4 $ 152.6 (a) As of March 31, 2019 , AEP Texas has deferred $137 million related to Hurricane Harvey. In March 2019, AEP Texas filed a request to securitize total estimated distribution-related system restoration costs with the PUCT. See “Texas Storm Cost Securitization” discussion below for additional information. APCo March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Plant Retirement Costs - Materials and Supplies $ 5.1 $ 9.0 Regulatory Assets Currently Not Earning a Return Plant Retirement Costs - Asset Retirement Obligation Costs 35.3 35.3 Other Regulatory Assets Pending Final Regulatory Approval — 0.6 Total Regulatory Assets Pending Final Regulatory Approval (a) $ 40.4 $ 44.9 (a) In 2015, APCo recorded a $91 million reduction to accumulated depreciation related to the remaining net book value of plants retired in 2015, primarily in its Virginia jurisdiction. These plants were normal retirements at the end of their depreciable lives under the group composite method of depreciation. APCo’s recovery of the remaining Virginia net book value for the retired plants will be considered in the Virginia SCC’s 2020 triennial review of APCo’s generation and distribution base rates. I&M March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Not Earning a Return Other Regulatory Assets Pending Final Regulatory Approval $ 3.4 $ 3.3 Total Regulatory Assets Pending Final Regulatory Approval $ 3.4 $ 3.3 OPCo March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Not Earning a Return Other Regulatory Assets Pending Final Regulatory Approval $ 0.1 $ 1.0 Total Regulatory Assets Pending Final Regulatory Approval $ 0.1 $ 1.0 PSO March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Oklaunion Power Station Accelerated Depreciation $ 10.9 $ 5.5 Total Regulatory Assets Pending Final Regulatory Approval $ 10.9 $ 5.5 SWEPCo March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Plant Retirement Costs - Unrecovered Plant $ 50.3 $ 50.3 Other Regulatory Assets Pending Final Regulatory Approval 0.3 0.3 Regulatory Assets Currently Not Earning a Return Asset Retirement Obligation - Arkansas, Louisiana 5.8 5.3 Rate Case Expense - Texas 0.9 4.9 Other Regulatory Assets Pending Final Regulatory Approval 3.7 3.6 Total Regulatory Assets Pending Final Regulatory Approval $ 61.0 $ 64.4 If these costs are ultimately determined not to be recoverable, it could reduce future net income and cash flows and impact financial condition. AEP Texas Rate Matters (Applies to AEP and AEP Texas) AEP Texas Interim Transmission and Distribution Rates As of March 31, 2019 , AEP Texas’ cumulative revenues from interim base rate increases from 2008 through 2018, subject to review, are estimated to be $1.1 billion . A base rate review could result in a refund to customers if AEP Texas incurs a disallowance of the transmission or distribution investment on which an interim increase was based. Management is unable to determine a range of potential losses, if any, that are reasonably possible of occurring. A revenue decrease, including a refund of interim transmission and distribution rates, could reduce future net income and cash flows and impact financial condition. In 2018, the PUCT adopted a rule requiring investor-owned utilities operating solely within ERCOT to make periodic filings for rate proceedings. The rule requires AEP Texas to file for a comprehensive rate review no later than May 1, 2019. Texas Storm Cost Securitization In August 2017, Hurricane Harvey hit the coast of Texas, causing power outages in the AEP Texas service territory. AEP Texas has a PUCT approved catastrophe reserve in base rates and can defer incremental storm expenses. AEP Texas currently recovers approximately $1 million of storm costs annually through base rates. As of March 31, 2019 , the total balance of AEP Texas’ regulatory asset for deferred storm costs is approximately $152 million , inclusive of approximately $137 million of incremental storm expenses related to Hurricane Harvey. In March 2019, AEP Texas filed a request to securitize total estimated distribution-related system restoration costs with the PUCT in the amount of $230 million , which includes estimated carrying costs. A decision by the PUCT is expected in the second quarter of 2019. See the table below for details of the request: Total Estimated Distribution-Related System Restoration Costs (in millions) Distribution-Related System Restoration Costs $ 264.6 Estimated Carrying Costs 26.9 Up-front Qualified Costs 4.6 Total Distribution-Related System Restoration Costs 296.1 less: Insurance Proceeds and Government Grants (3.1 ) Excess ADIT (a) (63.5 ) Total Requested Distribution-Related System Restoration Costs $ 229.5 (a) Amount represents Non-Hurricane Harvey Excess ADIT that is not subject to rate normalization requirements. The remaining $95 million of estimated net transmission-related system restoration costs, including carrying charges, is expected to be recovered through interim transmission filings or an upcoming base rate case. If these costs are not recovered, it could have an adverse effect on future net income, cash flows and financial condition. APCo and WPCo Rate Matters (Applies to AEP and APCo) Virginia Legislation Affecting Earnings Reviews Under a 2015 amended Virginia law, APCo’s existing generation and distribution base rates were frozen until after the Virginia SCC ruled on APCo’s next biennial review. The 2015 amendments also precluded the Virginia SCC from performing biennial reviews of APCo’s earnings for the years 2014 through 2017. New Virginia legislation impacting investor-owned utilities was enacted, effective July 1, 2018, that require APCo to file its next generation and distribution base rate case by March 31, 2020 using 2017, 2018 and 2019 earnings test years (“triennial review”). Triennial reviews are subject to an earnings test which provides that 70% of any earnings exceeding 70 basis points over the Virginia SCC authorized return on common equity would be refunded to customers. In November 2018, the Virginia SCC approved a return on common equity of 9.42% applicable to APCo base rate earnings for the 2017-2019 triennial period and rate adjustment clauses from November 2018 through November 2020. Management has reviewed APCo’s actual and forecasted earnings for the triennial period and concluded that it is not probable but is reasonably possible that APCo will over-earn in Virginia during the 2017-2019 triennial period. Due to various uncertainties, including weather, storm restoration, weather-normalized demand and potential customer shopping during 2019, management cannot estimate a range of potential APCo Virginia over-earnings during the 2017-2019 triennial period. The Virginia triennial review of APCo earnings could materially reduce future net income and cash flows and impact financial condition. Virginia Staff Depreciation Study Request In November 2018, Virginia staff recommended that APCo implement new Virginia jurisdictional depreciation rates effective January 1, 2018 based on APCo’s depreciation study that was prepared at Virginia staff’s request using December 31, 2017 APCo property balances. Implementation of those depreciation rates would result in a $21 million pretax increase in annual depreciation expense ( $6 million related to transmission) with no corresponding increase in retail base rates. In December 2018, APCo submitted a response to the Virginia staff stating that it was inappropriate for APCo to change Virginia depreciation rates in advance of the Virginia SCC’s upcoming Triennial Review of APCo, citing the Virginia SCC’s November 2014 order to not change APCo’s Virginia depreciation rates until APCo’s next base rate case/review. If the Virginia SCC were to issue an order approving the Virginia staff’s recommended retroactive change in APCo’s Virginia depreciation rates, it would reduce future net income and cash flows and impact financial condition. Virginia Tax Reform In March 2019, the Virginia SCC issued an order to reduce APCo’s base rates to refund: (a) $40 million annually for ongoing annual tax savings, (b) $9 million annually of Excess ADIT associated with certain depreciable property using ARAM, (c) $94 million of Excess ADIT that is not subject to rate normalization requirements over three years and (d) a one-time credit of $22 million for estimated excess taxes collected from customers during the 15-month period ending March 31, 2019. 2018 West Virginia Base Rate Case In May 2018, APCo and WPCo filed a joint request with the WVPSC to increase their combined West Virginia base rates by $115 million ( $98 million related to APCo) annually based on a 10.22% return on common equity. The proposed annual increase included $32 million ( $28 million related to APCo) due to increased annual depreciation expense and reflected the impact of the reduction in the federal income tax rate due to Tax Reform. In October 2018, APCo and WPCo filed updated schedules supporting a $95 million ( $80 million related to APCo) annual increase in West Virginia base rates primarily due to the impact of West Virginia Tax Reform. In February 2019, the WVPSC issued an order approving a Stipulation and Settlement agreement between APCo, WPCo, WVPSC staff and certain intervenors. The agreement included an annual base rate increase of $44 million ( $36 million related to APCo) based upon a 9.75% return on common equity effective March 2019. The agreement also included: (a) $18 million ( $14 million related to APCo) of increased annual depreciation expense, (b) a $24 million refund ( $19 million related to APCo) over two years, through a rider beginning March 2019, of Excess ADIT that is not subject to rate normalization requirements, (c) the utilization of $14 million ( $12 million related to APCo) of Excess ADIT that is not subject to rate normalization requirements to offset regulatory asset balances relating to ENEC, (d) an agreement to seek WVPSC approval of economic incentive programs to provide funds to aid in industrial and commercial development and (e) an agreement, barring any unforeseen events, to not initiate another base rate proceeding prior to April 1, 2020. ETT Rate Matters (Applies to AEP) ETT Interim Transmission Rates AEP has a 50% equity ownership interest in ETT. Predominantly all of ETT’s revenues are based on interim rate changes that can be filed twice annually and are subject to review and possible true-up in the next filed base rate proceeding. Through March 31, 2019 , AEP’s share of ETT’s cumulative revenues that are subject to review is estimated to be $918 million . A base rate review could produce a refund if ETT incurs a disallowance of the transmission investment on which an interim increase was based. A revenue decrease, including a refund of interim transmission rates, could reduce future net income and cash flows and impact financial condition. Management is unable to determine a range of potential losses, if any, that are reasonably possible of occurring. In 2018, the PUCT adopted a rule requiring investor-owned utilities operating solely inside ERCOT to make periodic filings for rate proceedings. The rule requires ETT to file for a comprehensive rate review no later than February 1, 2021. I&M Rate Matters (Applies to AEP and I&M) Michigan Tax Reform In October 2018, I&M made a filing with the MPSC recommending to: (a) refund approximately $68 million of Excess ADIT associated with certain depreciable property using ARAM and (b) refund approximately $37 million of Excess ADIT that is not subject to rate normalization requirements over ten years. An order from the MPSC regarding Excess ADIT is expected in the second half of 2019. OPCo Rate Matters (Applies to AEP and OPCo) Ohio Electric Security Plan Filings ESP Extension through 2024 In 2016, OPCo refiled its amended ESP extension application and supporting testimony, consistent with the terms of the modified and approved stipulation agreement and based upon a 2016 PUCO order. The amended filing proposed to extend the ESP through May 2024. In 2017, OPCo and various intervenors filed a stipulation agreement with the PUCO. The stipulation extends the term of the ESP through May 2024 and includes: (a) an extension of the OVEC PPA rider, (b) a proposed 10% return on common equity on capital costs for certain riders, (c) the continuation of riders previously approved in the June 2015 - May 2018 ESP, (d) rate caps related to OPCo’s DIR ranging from $215 million to $290 million for the periods 2018 through 2021 and (e) the addition of various new riders, including a Smart City Rider and a Renewable Generation Rider. DIR rate caps will be reset in OPCo’s next distribution base rate case which must be filed by June 2020. In April 2018, the PUCO issued an order approving the ESP extension stipulation agreement, with no significant changes. In October 2018, an intervenor filed an appeal with the Ohio Supreme Court challenging various approved riders. If the Ohio Supreme Court reverses the PUCO’s decision, it could reduce future net income and cash flows and impact financial condition. OPCo’s Enhanced Service Reliability Rider authorized under the ESP is subject to annual audits. In May 2018, the PUCO staff filed comments indicating that 2016 spending was subject to authorized limits and that OPCo overspent those limits. OPCo filed reply comments objecting to the PUCO staff’s position, including the method of the calculating the overspent amount. In March 2019, the PUCO staff filed additional comments which adjusted the method of the calculation but maintained that OPCo overspent the authorized limit in 2016 and 2017, which could result in a refund of $10 million . Management believes that the 2016 or 2017 spending is not subject to an authorized limit and that a spending limit was not established until 2018, as part of the ESP extension. A hearing has been set for May 2019 to address the 2016 audit. If it is determined OPCo did have an authorized spending limit in 2016 and 2017, and refunds are ordered, it would reduce future net income and cash flows and impact financial condition. 2016 SEET Filing Ohio law provides for the return of significantly excessive earnings to ratepayers upon PUCO review. Significantly excessive earnings are measured by whether the earned return on common equity of the electric utility is significantly in excess of the return on common equity that was earned during the same period by publicly traded companies, including utilities, that face comparable business and financial risk. In 2016, OPCo recorded a 2016 SEET provision of $58 million based upon projected earnings data for companies in the comparable utilities risk group. In determining OPCo’s return on equity in relation to the comparable utilities risk group, management excluded the following items resolved in OPCo’s Global Settlement that was filed at the PUCO in December 2016 and subsequently approved in February 2017: (a) gain on the deferral of RSR costs, (b) refunds to customers related to the SEET remands and (c) refunds to customers related to fuel adjustment clause proceedings. In February 2019, the PUCO issued an order that OPCo did not have significantly excessive earnings in 2016. As a result of the order, OPCo reversed the $58 million provision in the first quarter of 2019. PSO Rate Matters (Applies to AEP and PSO) 2018 Oklahoma Base Rate Case In October 2018, PSO filed a request with the OCC for an $88 million annual increase in Oklahoma retail rates based upon a 10.3% return on common equity. PSO also proposed to implement a performance-based rate plan that combines a formula rate with a set of customer-focused performance incentive measures related to reliability, public safety, customer satisfaction and economic development. The proposed annual increase included $13 million related to increased annual depreciation rates and $7 million related to increased storm expense amortization. The requested increase in annual depreciation rates includes the recovery of Oklaunion Power Station through 2028 (currently being recovered in rates through 2046). Management has announced plans to retire Oklaunion Power Station by October 2020. In March 2019, the OCC issued an order approving a Stipulation and Settlement agreement for a $46 million annual increase, based on a 9.4% return on equity effective with the first billing cycle of April 2019. The order also included agreements between the parties that: (a) depreciation rates will remain unchanged, (b) PSO will file a new base rate request no earlier than October 2020 and no later than October 2021 and (c) PSO will refund Excess ADIT that is not subject to rate normalization requirements over five years instead of the ten years ordered in the Oklahoma Tax Reform case. The order did not approve the performance-based rate plan but instead provided for an expansion of the SPP Transmission Tariff that tracks previously untracked SPP costs and a new Distribution Reliability and Safety Rider that provides additional revenues capped at $5 million per year for distribution projects related to safety and reliability that are not normal distribution replacements. SWEPCo Rate Matters (Applies to AEP and SWEPCo) 2012 Texas Base Rate Case In 2012, SWEPCo filed a request with the PUCT to increase annual base rates primarily due to the completion of the Turk Plant. In 2013, the PUCT issued an order affirming the prudence of the Turk Plant but determined that the Turk Plant’s Texas jurisdictional capital cost cap established in a previous Certificate of Convenience and Necessity case also limited SWEPCo’s recovery of AFUDC in addition to limits on its recovery of cash construction costs. Upon rehearing in 2014, the PUCT reversed its initial ruling and determined that AFUDC was excluded from the Turk Plant’s Texas jurisdictional capital cost cap. As a result, SWEPCo reversed $114 million of a previously recorded regulatory disallowance in 2013. The resulting annual base rate increase was approximately $52 million . In 2017, the Texas District Court upheld the PUCT’s 2014 order and intervenors filed appeals with the Texas Third Court of Appeals. In July 2018, the Texas Third Court of Appeals reversed the PUCT’s judgment affirming the prudence of the Turk Plant and remanded the issue back to the PUCT. In August 2018, SWEPCo filed a Motion for Reconsideration at the Court of Appeals, which was denied. In January 2019, SWEPCo and the PUCT filed petitions for review with the Texas Supreme Court, which has ordered appellants to file responses by May 29, 2019. As of March 31, 2019 , the net book value of Turk Plant was $1.5 billion , before cost of removal, including materials and supplies inventory and CWIP. If certain parts of the PUCT order are overturned and if SWEPCo cannot ultimately fully recover its approximate 33% Texas jurisdictional share of the Turk Plant investment, including AFUDC, it could reduce future net income and cash flows and impact financial condition. 2016 Texas Base Rate Case In 2016, SWEPCo filed a request with the PUCT for a net increase in Texas annual revenues of $69 million based upon a 10% return on common equity. In January 2018, the PUCT issued a final order approving a net increase in Texas annual revenues of $50 million based upon a return on common equity of 9.6% , effective May 2017. The final order also included: (a) approval to recover the Texas jurisdictional share of environmental investments placed in- service, as of June 30, 2016, at various plants, including Welsh Plant, Units 1 and 3, (b) approval of recovery of, but no return on, the Texas jurisdictional share of the net book value of Welsh Plant, Unit 2, (c) approval of $2 million in additional vegetation management expenses and (d) the rejection of SWEPCo’s proposed transmission cost recovery mechanism. As a result of the final order, in 2017 SWEPCo: (a) recorded an impairment charge of $19 million , which included $7 million associated with the lack of return on Welsh Plant, Unit 2 and $12 million related to other disallowed plant investments, (b) recognized $32 million of additional revenues, for the period of May 2017 through December 2017, that was surcharged to customers in 2018 and (c) recognized an additional $7 million of expenses consisting primarily of depreciation expense and vegetation management expense, offset by the deferral of rate case expense. SWEPCo implemented new rates in February 2018 billings. The $32 million of additional 2017 revenues was collected during 2018. In March 2018, the PUCT clarified and corrected portions of the final order, without changing the overall decision or amounts of the rate change. The order has been appealed by various intervenors. If certain parts of the PUCT order are overturned, it could reduce future net income and cash flows and impact financial condition. 2018 Louisiana Formula Rate Filing In April 2018, SWEPCo filed its formula rate plan for test year 2017 with the LPSC. The filing included a net $28 million annual increase, which was effective August 2018 and included SWEPCo’s Louisiana jurisdictional share of Welsh Plant and Flint Creek Plant environmental controls. The filing also included a reduction in the federal income tax rate due to Tax Reform but did not address the return of Excess ADIT benefits to customers. In July 2018, SWEPCo made a supplemental filing to its formula rate plan with the LPSC to reduce the requested annual increase to $18 million . The difference between SWEPCo’s requested $28 million annual increase and the $18 million annual increase in the supplemental filing is primarily the result of the return of Excess ADIT benefits to customers. In October 2018, the LPSC staff issued a recommendation that SWEPCo refund $11 million of excess federal income taxes collected, as a result of Tax Reform, from January 1, 2018 through July 31, 2018. A decision by the LPSC is expected in 2019. If any of these costs are not recoverable, it could reduce future net income and cash flows and impact financial condition. Welsh Plant - Environmental Impact Management currently estimates that the investment necessary to meet proposed environmental regulations through 2025 for Welsh Plant, Units 1 and 3 could total approximately $550 million , excluding AFUDC. As of March 31, 2019 , SWEPCo had incurred costs of $399 million , including AFUDC, related to these projects. Management continues to evaluate the impact of environmental rules and related project cost estimates. As of March 31, 2019 , the total net book value of Welsh Plant, Units 1 and 3 was $623 million , before cost of removal, including materials and supplies inventory and CWIP. In 2016, as approved by the APSC, SWEPCo began recovering $79 million related to the Arkansas jurisdictional share of these environmental costs, subject to prudence review in the next Arkansas filed base rate proceeding. In 2017, the LPSC approved recovery of $131 million in investments related to its Louisiana jurisdictional share of environmental controls installed at Welsh Plant. SWEPCo’s approved Louisiana jurisdictional share of Welsh Plant deferrals: (a) are $10 million , excluding $5 million of unrecognized equity as of March 31, 2019, (b) is subject to review by the LPSC and (c) includes a weighted average cost of capital return on environmental investments and the related depreciation expense and taxes. See “2018 Louisiana Formula Rate Filing” disclosure above for additional information. If any of these costs are not recoverable, it could reduce future net income and cash flows and impact financial condition. 2019 Arkansas Base Rate Case In February 2019, SWEPCo filed a request with the APSC for a $75 million increase in Arkansas base rates based upon a proposed 10.5% return on common equity. The filing requests rate base treatment for the Stall Plant and the environmental retrofits that are currently being recovered through riders. Eliminating these riders would result in a net annual requested base rate increase of $58 million . The proposed net annual increase includes $12 million related to vegetation management to improve the reliability of its Arkansas distribution system. The filing also provides notice of SWEPCo’s proposal to have its rates regulated under the formula rate review mechanism authorized by Arkansas Act 725 of 2015, including a Formula Rate Review Rider. If any of these costs are not recoverable, it could reduce future net income and cash flows and impact financial condition. FERC Rate Matters FERC Transmission Complaint - AEP’s PJM Participants (Applies to AEP, AEPTCo, APCo, I&M and OPCo) In 2016, seven parties filed a complaint at the FERC that alleged the base return on common equity used by AEP’s transmission owning subsidiaries within PJM in calculating formula transmission rates under the PJM OATT is excessive and should be reduced from 10.99% to 8.32% , effective upon the date of the complaint. In March 2018, AEP’s transmission owning subsidiaries within PJM and six of the complainants filed a settlement agreement with the FERC (the seventh complainant abstained). If approved by the FERC, the settlement agreement: (a) establishes a base ROE for AEP’s transmission owning subsidiaries within PJM of 9.85% ( 10.35% inclusive of the RTO incentive adder of 0.5% ), effective January 1, 2018, (b) requires AEP’s transmission owning subsidiaries within PJM to provide a one-time refund of $50 million , attributable from the date of the complaint through December 31, 2017, which was credited to customer bills in the second quarter of 2018 and (c) increases the cap on the equity portion of the capital structure to 55% from 50% . As part of the settlement agreement, AEP’s transmission owning subsidiaries within PJM also filed updated transmission formula rates incorporating the reduction in the corporate federal income tax rate due to Tax Reform, effective January 1, 2018 and providing for the amortization of the portion of the Excess ADIT that is not subject to the normalization method of accounting, ratably over a ten-year period through credits to the federal income tax expense component of the revenue requirement. In April 2018, an ALJ accepted the interim settlement rates. These interim rates are subject to refund or surcharge, with interest. Also in April 2018, certain intervenors filed comments at the FERC recommending a lower ROE. In March 2019, the intervenors subsequently withdrew their opposition to the settlement and the settling parties filed a joint motion at the FERC seeking approval of this now uncontested settlement. A decision from the FERC is pending. If the FERC orders revenue reductions in excess of the terms of the settlement agreement, it could reduce future net income and cash flows and impact financial condition. FERC Transmission Complaint - AEP’s SPP Participants (Applies to AEP, AEPTCo, PSO and SWEPCo) In 2017, several parties filed a complaint at the FERC that states the base return on common equity used by AEP’s transmission owning subsidiaries within SPP in calculating formula transmission rates under the SPP OATT is excessive and should be reduced from 10.7% to 8.36% , effective upon the date of the complaint through September 5, 2018. A FERC order set the matter for hearing and settlement procedures. In September 2018, the same parties filed another complaint at the FERC that states the base return on common equity used by AEP’s transmission owning subsidiaries within SPP in calculating formula transmission rates under the SPP OATT is excessive and should be reduced from 10.7% to 8.71% , effective upon the date of the second complaint. In March 2019, AEP’s transmission owning subsidiaries within SPP and the complainants filed an unopposed settlement agreement with the FERC that establishes a base ROE of 10% ( 10.50% inclusive of the RTO incentive adder of 0.5% ) effective January 1, 2019. Additionally, if approved, refunds including carrying charges would be made from the date of the first complaint through December 31, 2018. Refunds for the period prior to 2019 would be made at the time of the 2019 true-up of 2018 rates. Refunds from January 2019 onward would begin following a FERC approval of the settlement and conclude with the 2020 true-up of 2019 rates. A decision from the FERC is pending. Management believes its financial statements adequately address the impact of the settlement. If the FERC orders further revenue reductions it could reduce future net income and cash flows and impact financial condition. Modifications to AEP’s SPP Transmission Rates (Applies to AEP, AEPTCo, PSO and SWEPCo)

Commitments, Guarantees and Con

Commitments, Guarantees and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments, Guarantees and Contingencies	COMMITMENTS, GUARANTEES AND CONTINGENCIES The disclosures in this note apply to all Registrants unless indicated otherwise. The Registrants are subject to certain claims and legal actions arising in the ordinary course of business. In addition, the Registrants’ business activities are subject to extensive governmental regulation related to public health and the environment. The ultimate outcome of such pending or potential litigation against the Registrants cannot be predicted. Management accrues contingent liabilities only when management concludes that it is both probable that a liability has been incurred at the date of the financial statements and the amount of loss can be reasonably estimated. When management determines that it is not probable, but rather reasonably possible that a liability has been incurred at the date of the financial statements, management discloses such contingencies and the possible loss or range of loss if such estimate can be made. Any estimated range is based on currently available information and involves elements of judgment and significant uncertainties. Any estimated range of possible loss may not represent the maximum possible loss exposure. Circumstances change over time and actual results may vary significantly from estimates. For current proceedings not specifically discussed below, management does not anticipate that the liabilities, if any, arising from such proceedings would have a material effect on the financial statements. The Commitments, Guarantees and Contingencies note within the 2018 Annual Report should be read in conjunction with this report. GUARANTEES Liabilities for guarantees are recorded in accordance with the accounting guidance for “Guarantees.” There is no collateral held in relation to any guarantees. In the event any guarantee is drawn, there is no recourse to third-parties unless specified below. Letters of Credit (Applies to AEP, AEP Texas and OPCo) Standby letters of credit are entered into with third-parties. These letters of credit are issued in the ordinary course of business and cover items such as natural gas and electricity risk management contracts, construction contracts, insurance programs, security deposits and debt service reserves. AEP has a $4 billion revolving credit facility due in June 2022, under which up to $1.2 billion may be issued as letters of credit on behalf of subsidiaries. As of March 31, 2019 , no letters of credit were issued under the revolving credit facility. An uncommitted facility gives the issuer of the facility the right to accept or decline each request made under the facility. AEP issues letters of credit on behalf of subsidiaries under four uncommitted facilities totaling $305 million . In April 2019, AEP executed two additional $50 million uncommitted letter of credit facilities. The Registrants’ maximum future payments for letters of credit issued under the uncommitted facilities as of March 31, 2019 were as follows: Company Amount Maturity (in millions) AEP $ 105.8 June 2019 to March 2020 AEP Texas 2.2 January 2020 OPCo 1.2 September 2019 to March 2020 AEP has $45 million of variable rate Pollution Control Bonds supported by $46 million of bilateral letters of credit maturing in July 2019. Guarantees of Third-Party Obligations (Applies to AEP and SWEPCo) As part of the process to receive a renewal of a Texas Railroad Commission permit for lignite mining, SWEPCo provides guarantees of mine reclamation of $140 million . Since SWEPCo uses self-bonding, the guarantee commits SWEPCo to complete the reclamation, in the event, Sabine does not complete the work. This guarantee ends upon depletion of reserves and completion of reclamation. The reserves are estimated to deplete in 2036 with reclamation completed by 2046 at an estimated cost of $107 million . Actual reclamation costs could vary due to inflation and scope changes to the mine reclamation. As of March 31, 2019 , SWEPCo has collected $76 million through a rider for reclamation costs, of which $82 million was recorded in Asset Retirement Obligations, offset by $6 million recorded in Deferred Charges and Other Noncurrent Assets on SWEPCo’s balance sheets. Sabine charges all of its costs to its only customer, SWEPCo, which recovers these costs through its fuel clauses. Guarantees of Equity Method Investees (Applies to AEP) In December 2016, AEP issued a performance guarantee for a 50% owned joint venture which is accounted for as an equity method investment. If the joint venture were to default on payments or performance, AEP would be required to make payments on behalf of the joint venture. As of March 31, 2019 , the maximum potential amount of future payments associated with this guarantee was $75 million , which expires in December 2019. Indemnifications and Other Guarantees Contracts The Registrants enter into certain types of contracts which require indemnifications. Typically these contracts include, but are not limited to, sale agreements, lease agreements, purchase agreements and financing agreements. Generally, these agreements may include, but are not limited to, indemnifications around certain tax, contractual and environmental matters. With respect to sale agreements, exposure generally does not exceed the sale price. As of March 31, 2019 , there were no material liabilities recorded for any indemnifications. AEPSC conducts power purchase-and-sale activity on behalf of APCo, I&M, KPCo and WPCo, who are jointly and severally liable for activity conducted on their behalf. AEPSC also conducts power purchase-and-sale activity on behalf of PSO and SWEPCo, who are jointly and severally liable for activity conducted on their behalf. ENVIRONMENTAL CONTINGENCIES (Applies to all Registrants except AEPTCo) The Comprehensive Environmental Response Compensation and Liability Act (Superfund) and State Remediation By-products from the generation of electricity include materials such as ash, slag, sludge, low-level radioactive waste and SNF. Coal combustion by-products, which constitute the overwhelming percentage of these materials, are typically treated and deposited in captive disposal facilities or are beneficially utilized. In addition, the generation plants and transmission and distribution facilities have used asbestos, polychlorinated biphenyls and other hazardous and non-hazardous materials. The Registrants currently incur costs to dispose of these substances safely. For remediation processes not specifically discussed, management does not anticipate that the liabilities, if any, arising from such remediation processes would have a material effect on the financial statements. NUCLEAR CONTINGENCIES (Applies to AEP and I&M) I&M owns and operates the two-unit 2,278 MW Cook Plant under licenses granted by the Nuclear Regulatory Commission. I&M has a significant future financial commitment to dispose of SNF and to safely decommission and decontaminate the plant. The licenses to operate the two nuclear units at the Cook Plant expire in 2034 and 2037. The operation of a nuclear facility also involves special risks, potential liabilities and specific regulatory and safety requirements. By agreement, I&M is partially liable, together with all other electric utility companies that own nuclear generation units, for a nuclear power plant incident at any nuclear plant in the U.S. Should a nuclear incident occur at any nuclear power plant in the U.S., the resultant liability could be substantial. OPERATIONAL CONTINGENCIES Rockport Plant Litigation (Applies to AEP and I&M) In 2013, the Wilmington Trust Company filed a complaint in the U.S. District Court for the Southern District of New York against AEGCo and I&M alleging that it would be unlawfully burdened by the terms of the modified NSR consent decree after the Rockport Plant, Unit 2 lease expiration in December 2022. The terms of the consent decree allow the installation of environmental emission control equipment, repowering, refueling or retirement of the unit. The plaintiffs seek a judgment declaring that the defendants breached the lease, must satisfy obligations related to installation of emission control equipment and indemnify the plaintiffs. The New York court granted a motion to transfer this case to the U.S. District Court for the Southern District of Ohio. AEGCo and I&M sought and were granted dismissal by the U.S. District Court for the Southern District of Ohio of certain of the plaintiffs’ claims, including claims for compensatory damages, breach of contract, breach of the implied covenant of good faith and fair dealing and indemnification of costs. Plaintiffs voluntarily dismissed the surviving claims that AEGCo and I&M failed to exercise prudent utility practices with prejudice, and the court issued a final judgment. The plaintiffs subsequently filed an appeal in the U.S. Court of Appeals for the Sixth Circuit. In 2017, the U.S. Court of Appeals for the Sixth Circuit issued an opinion and judgment affirming the district court’s dismissal of the owners’ breach of good faith and fair dealing claim as duplicative of the breach of contract claims, reversing the district court’s dismissal of the breach of contract claims and remanding the case for further proceedings. Thereafter, AEP filed a motion with the U.S. District Court for the Southern District of Ohio in the original NSR litigation, seeking to modify the consent decree. The district court granted the owners’ unopposed motion to stay the lease litigation to afford time for resolution of AEP’s motion to modify the consent decree. In September 2018, the district court granted AEP’s unopposed motion to stay further proceedings regarding the consent decree to facilitate settlement discussions among the parties to the consent decree. See “Proposed Modification of the NSR Litigation Consent Decree” section of Management’s Discussion and Analysis of Financial Condition and Results of Operations for additional information.

Acquisitions and Impairments

Acquisitions and Impairments	3 Months Ended
	Mar. 31, 2019
Impairment, Disposition and Assets and Liabilities Held for Sale	IMPAIRMENTS The disclosures in this note apply to AEP unless indicated otherwise. ACQUISITIONS Sempra Renewables LLC (Generation & Marketing Segment) In April 2019, AEP acquired Sempra Renewables LLC and its 724 MWs of wind generation and battery assets for approximately $1.1 billion , subject to working capital adjustments. AEP paid $584 million in cash and assumed approximately $358 million of existing project debt obligations of the non-consolidated joint ventures. Additionally, the acquisition includes the recognition of noncontrolling tax equity interest of an estimated $110 million as of the acquisition date associated with certain of the acquired wind farms. The purchase price will be allocated primarily to equity method investment (included in Deferred Charges and Other Noncurrent Assets) and Property, Plant and Equipment on AEP’s balance sheets. AEP has issued guarantees and letters of credit in relation to the acquisition to support project debt and other requirements. The wind generation portfolio includes seven wholly or jointly-owned wind farms with long-term PPAs for 100% of their energy production. Two of the jointly-owned wind farms have PPAs with I&M, OPCo and SWEPCo for a portion of their energy production and are accounted for under the accounting guidance for “Regulated Operations.” If the Sempra acquisition would have been completed prior to the Balance Sheet date, the revenue and earnings impact would have been immaterial to AEP for the three months ended March 31, 2019 and 2018 , respectively. IMPAIRMENTS Other Assets (Corporate and Other) (Vertically Integrated Utilities Segment) (Applies to AEP and APCo) In the first quarter of 2018, AEP was notified by an equity investee that it had ceased operations. AEP recorded a pretax impairment of $21 million

Benefit Plans

Benefit Plans	3 Months Ended
	Mar. 31, 2019
Benefit Plans	BENEFIT PLANS The disclosures in this note apply to all Registrants except AEPTCo unless indicated otherwise. AEP sponsors a qualified pension plan and two unfunded non-qualified pension plans. Substantially all AEP employees are covered by the qualified plan or both the qualified and a non-qualified pension plan. AEP also sponsors OPEB plans to provide health and life insurance benefits for retired employees. Components of Net Periodic Benefit Cost The following tables provide the components of net periodic benefit cost (credit) by Registrant for the plans: AEP Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 23.9 $ 24.4 $ 2.4 $ 2.9 Interest Cost 51.1 46.9 12.6 11.8 Expected Return on Plan Assets (74.0 ) (72.5 ) (23.4 ) (25.5 ) Amortization of Prior Service Credit — — (17.3 ) (17.3 ) Amortization of Net Actuarial Loss 14.4 21.3 5.5 2.6 Net Periodic Benefit Cost (Credit) $ 15.4 $ 20.1 $ (20.2 ) $ (25.5 ) AEP Texas Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.1 $ 2.3 $ 0.2 $ 0.3 Interest Cost 4.4 4.0 1.0 0.9 Expected Return on Plan Assets (6.4 ) (6.4 ) (2.0 ) (2.1 ) Amortization of Prior Service Credit — — (1.5 ) (1.5 ) Amortization of Net Actuarial Loss 1.2 1.8 0.5 0.2 Net Periodic Benefit Cost (Credit) $ 1.3 $ 1.7 $ (1.8 ) $ (2.2 ) APCo Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.4 $ 2.3 $ 0.3 $ 0.3 Interest Cost 6.3 5.9 2.2 2.0 Expected Return on Plan Assets (9.4 ) (9.1 ) (3.7 ) (4.0 ) Amortization of Prior Service Credit — — (2.5 ) (2.5 ) Amortization of Net Actuarial Loss 1.8 2.6 0.9 0.5 Net Periodic Benefit Cost (Credit) $ 1.1 $ 1.7 $ (2.8 ) $ (3.7 ) I&M Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 3.4 $ 3.4 $ 0.3 $ 0.4 Interest Cost 6.0 5.5 1.5 1.4 Expected Return on Plan Assets (9.2 ) (8.9 ) (2.8 ) (3.1 ) Amortization of Prior Service Credit — — (2.4 ) (2.4 ) Amortization of Net Actuarial Loss 1.6 2.5 0.7 0.3 Net Periodic Benefit Cost (Credit) $ 1.8 $ 2.5 $ (2.7 ) $ (3.4 ) OPCo Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.0 $ 2.0 $ 0.2 $ 0.2 Interest Cost 4.7 4.4 1.4 1.3 Expected Return on Plan Assets (7.3 ) (7.2 ) (2.7 ) (3.0 ) Amortization of Prior Service Credit — — (1.7 ) (1.7 ) Amortization of Net Actuarial Loss 1.3 2.0 0.6 0.3 Net Periodic Benefit Cost (Credit) $ 0.7 $ 1.2 $ (2.2 ) $ (2.9 ) PSO Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 1.6 $ 1.8 $ 0.2 $ 0.2 Interest Cost 2.6 2.4 0.7 0.6 Expected Return on Plan Assets (4.1 ) (4.0 ) (1.3 ) (1.4 ) Amortization of Prior Service Credit — — (1.1 ) (1.0 ) Amortization of Net Actuarial Loss 0.8 1.1 0.3 0.1 Net Periodic Benefit Cost (Credit) $ 0.9 $ 1.3 $ (1.2 ) $ (1.5 ) SWEPCo Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.1 $ 2.3 $ 0.2 $ 0.3 Interest Cost 3.1 2.9 0.8 0.7 Expected Return on Plan Assets (4.4 ) (4.4 ) (1.5 ) (1.6 ) Amortization of Prior Service Credit — — (1.3 ) (1.3 ) Amortization of Net Actuarial Loss 0.9 1.3 0.3 0.1 Net Periodic Benefit Cost (Credit) $ 1.7 $ 2.1 $ (1.5 ) $ (1.8 )

Business Segments

Business Segments	3 Months Ended
	Mar. 31, 2019
Business Segments	8 . BUSINESS SEGMENTS The disclosures in this note apply to all Registrants unless indicated otherwise. AEP’s Reportable Segments AEP’s primary business is the generation, transmission and distribution of electricity. Within its Vertically Integrated Utilities segment, AEP centrally dispatches generation assets and manages its overall utility operations on an integrated basis because of the substantial impact of cost-based rates and regulatory oversight. Intersegment sales and transfers are generally based on underlying contractual arrangements and agreements. AEP’s reportable segments and their related business activities are outlined below: Vertically Integrated Utilities • Generation, transmission and distribution of electricity for sale to retail and wholesale customers through assets owned and operated by AEGCo, APCo, I&M, KGPCo, KPCo, PSO, SWEPCo and WPCo. Transmission and Distribution Utilities • Transmission and distribution of electricity for sale to retail and wholesale customers through assets owned and operated by AEP Texas and OPCo. • OPCo purchases energy and capacity to serve SSO customers and provides transmission and distribution services for all connected load. AEP Transmission Holdco • Development, construction and operation of transmission facilities through investments in AEPTCo. These investments have FERC-approved returns on equity. • Development, construction and operation of transmission facilities through investments in AEP’s transmission-only joint ventures. These investments have PUCT-approved or FERC-approved returns on equity. Generation & Marketing • Competitive generation in ERCOT and PJM. • Marketing, risk management and retail activities in ERCOT, PJM, SPP and MISO. • Contracted renewable energy investments and management services. The remainder of AEP’s activities is presented as Corporate and Other. While not considered a reportable segment, 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, interest expense, income tax expense and other nonallocated costs. The tables below present AEP’s reportable segment income statement information for the three months ended March 31, 2019 and 2018 and reportable segment balance sheet information as of March 31, 2019 and December 31, 2018 . Three Months Ended March 31, 2019 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Adjustments Consolidated (in millions) Revenues from: External Customers $ 2,372.3 $ 1,179.8 $ 61.2 $ 439.7 $ 3.8 $ — $ 4,056.8 Other Operating Segments 31.0 42.2 195.2 42.1 21.7 (332.2 ) — Total Revenues $ 2,403.3 $ 1,222.0 $ 256.4 $ 481.8 $ 25.5 $ (332.2 ) $ 4,056.8 Net Income (Loss) $ 303.6 $ 156.5 $ 125.2 $ 39.2 $ (50.4 ) $ — $ 574.1 Three Months Ended March 31, 2018 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Adjustments Consolidated (in millions) Revenues from: External Customers $ 2,381.5 $ 1,141.2 $ 41.1 $ 477.5 $ 7.0 $ — $ 4,048.3 Other Operating Segments 26.5 21.2 164.4 27.6 17.0 (256.7 ) — Total Revenues $ 2,408.0 $ 1,162.4 $ 205.5 $ 505.1 $ 24.0 $ (256.7 ) $ 4,048.3 Net Income (Loss) $ 232.8 $ 125.4 $ 104.8 $ 18.1 $ (24.4 ) $ — $ 456.7 March 31, 2019 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Consolidated (in millions) Total Property, Plant and Equipment $ 45,684.3 $ 18,526.1 $ 8,973.2 $ 915.6 $ 406.4 $ (354.4 ) (b) $ 74,151.2 Accumulated Depreciation and Amortization 13,944.5 3,856.1 318.8 58.7 190.9 (186.4 ) (b) 18,182.6 Total Property Plant and Equipment - Net $ 31,739.8 $ 14,670.0 $ 8,654.4 $ 856.9 $ 215.5 $ (168.0 ) (b) $ 55,968.6 Total Assets $ 40,085.7 $ 17,419.0 $ 9,790.2 $ 1,960.1 $ 4,341.2 (c) $ (2,874.2 ) (b) (d) $ 70,722.0 Long-term Debt Due Within One Year: Nonaffiliated $ 912.1 533.3 85.0 — (1.9 ) (e) — $ 1,528.5 Long-term Debt: Affiliated 50.0 — — 32.2 — (82.2 ) — Nonaffiliated 11,999.5 4,938.6 2,895.3 (0.3 ) 3,065.1 — 22,898.2 Total Long-term Debt $ 12,961.6 $ 5,471.9 $ 2,980.3 $ 31.9 $ 3,063.2 (e) $ (82.2 ) $ 24,426.7 December 31, 2018 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Consolidated (in millions) Total Property, Plant and Equipment $ 45,365.1 $ 18,126.7 $ 8,659.5 $ 893.3 $ 395.2 $ (354.6 ) (b) $ 73,085.2 Accumulated Depreciation and Amortization 13,822.5 3,833.7 282.8 47.0 186.6 (186.5 ) (b) 17,986.1 Total Property Plant and Equipment - Net $ 31,542.6 $ 14,293.0 $ 8,376.7 $ 846.3 $ 208.6 $ (168.1 ) (b) $ 55,099.1 Total Assets $ 38,874.3 $ 17,083.4 $ 9,543.7 $ 1,979.7 $ 4,036.5 (c) $ (2,714.8 ) (b) (d) $ 68,802.8 Long-term Debt Due Within One Year: Nonaffiliated $ 1,066.3 $ 549.1 $ 85.0 $ 0.1 $ (2.0 ) (e) $ — $ 1,698.5 Long-term Debt: Affiliated 50.0 — — 32.2 — (82.2 ) — Nonaffiliated 11,442.7 5,048.8 2,888.6 (0.3 ) 2,268.4 — 21,648.2 Total Long-term Debt $ 12,559.0 $ 5,597.9 $ 2,973.6 $ 32.0 $ 2,266.4 (e) $ (82.2 ) $ 23,346.7 (a) Corporate and Other primarily includes the purchasing of receivables from certain AEP utility subsidiaries. This segment also includes 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 finance lease. (c) Includes elimination of AEP Parent’s investments in wholly-owned subsidiary companies. (d) Reconciling Adjustments for Total Assets primarily include elimination of intercompany advances to affiliates and intercompany accounts receivable. (e) Amounts reflect the impact of fair value hedge accounting. See “Accounting for Fair Value Hedging Strategies” section of Note 10 for additional information. Registrant Subsidiaries’ Reportable Segments (Applies to all Registrant Subsidiaries except AEPTCo) The Registrant Subsidiaries each have one reportable segment, an integrated electricity generation, transmission and distribution business for APCo, I&M, PSO and SWEPCo and an integrated electricity transmission and distribution business for AEP Texas and OPCo. Other activities are insignificant. The Registrant Subsidiaries’ operations are managed on an integrated basis because of the substantial impact of cost-based rates and regulatory oversight on the business process, cost structures and operating results. AEPTCo’s Reportable Segments AEPTCo Parent is the holding company of the State Transcos. The State Transcos have been identified as operating segments of AEPTCo under the accounting guidance for “Segment Reporting.” The State Transcos business consists of developing, constructing and operating transmission facilities at the request of the RTOs in which they operate and in replacing and upgrading facilities, assets and components of the existing AEP transmission system as needed to maintain reliability standards and provide service to AEP’s wholesale and retail customers. The State Transcos are regulated for rate-making purposes exclusively by the FERC and earn revenues through tariff rates charged for the use of their electric transmission systems. AEPTCo’s Chief Operating Decision Maker makes operating decisions, allocates resources to and assesses performance based on these operating segments. The State Transcos operating segments all have similar economic characteristics and meet all of the criteria under the accounting guidance for “Segment Reporting” to be aggregated into one operating segment. As a result, AEPTCo has one reportable segment. The remainder of AEPTCo’s activity is presented in AEPTCo Parent. While not considered a reportable segment, AEPTCo Parent represents the activity of the holding company which primarily relates to debt financing activity and general corporate activities. The tables below present AEPTCo’s reportable segment statements of income information for the three months ended March 31, 2019 and 2018 and reportable segment balance sheet information as of March 31, 2019 and December 31, 2018 . Three Months Ended March 31, 2019 State Transcos AEPTCo Parent Reconciling Adjustments AEPTCo Consolidated (in millions) Revenues from: External Customers $ 50.3 $ — $ — $ 50.3 Sales to AEP Affiliates 193.2 — — 193.2 Total Revenues $ 243.5 $ — $ — $ 243.5 Interest Income $ 0.2 $ 28.4 $ (27.9 ) (a) $ 0.7 Interest Expense 21.7 27.9 (27.9 ) (a) 21.7 Income Tax Expense 27.6 — — 27.6 Net Income $ 104.2 $ 0.1 (b) — $ 104.3 Three Months Ended March 31, 2018 State Transcos (f) AEPTCo Parent Reconciling Adjustments AEPTCo Consolidated (f) (in millions) Revenues from: External Customers $ 30.9 $ — $ — $ 30.9 Sales to AEP Affiliates 160.7 — — 160.7 Other Revenues 0.1 — — 0.1 Total Revenues $ 191.7 $ — $ — $ 191.7 Interest Income $ 0.2 $ 25.0 $ (24.8 ) (a) $ 0.4 Interest Expense 20.3 24.8 (24.8 ) (a) 20.3 Income Tax Expense 21.7 0.3 — 22.0 Net Income $ 84.1 $ — $ — $ 84.1 March 31, 2019 State Transcos AEPTCo Parent Reconciling Adjustments AEPTCo (in millions) Total Transmission Property $ 8,567.2 $ — $ — $ 8,567.2 Accumulated Depreciation and Amortization 306.7 — — 306.7 Total Transmission Property – Net $ 8,260.5 $ — $ — $ 8,260.5 Notes Receivable – Affiliated $ — $ 2,823.4 $ (2,823.4 ) (c) $ — Total Assets $ 8,584.0 $ 2,928.1 (d) $ (2,896.0 ) (e) $ 8,616.1 Total Long-term Debt $ 2,850.0 $ 2,823.4 $ (2,850.0 ) (c) $ 2,823.4 December 31, 2018 State Transcos AEPTCo Parent Reconciling Adjustments AEPTCo (in millions) Total Transmission Property $ 8,268.1 $ — $ — $ 8,268.1 Accumulated Depreciation and Amortization 271.9 — — 271.9 Total Transmission Property – Net $ 7,996.2 $ — $ — $ 7,996.2 Notes Receivable – Affiliated $ — $ 2,823.0 $ (2,823.0 ) (c) $ — Total Assets $ 8,406.8 $ 2,857.1 (d) $ (2,869.8 ) (e) $ 8,394.1 Total Long-term Debt $ 2,850.0 $ 2,823.0 $ (2,850.0 ) (c) $ 2,823.0 (a) Elimination of intercompany interest income/interest expense on affiliated debt arrangement. (b) Includes the elimination of AEPTCo Parent’s equity earnings in the State Transcos. (c) Elimination of intercompany debt. (d) Includes the elimination of AEPTCo Parent’s investments in State Transcos. (e) Primarily relates to the elimination of Notes Receivable from the State Transcos. (f)

Derivatives and Hedging

Derivatives and Hedging	3 Months Ended
	Mar. 31, 2019
Derivatives and Hedging	DERIVATIVES AND HEDGING The disclosures in this note apply to all Registrants unless indicated otherwise. For the periods presented, AEPTCo did not have any derivative and hedging activity. OBJECTIVES FOR UTILIZATION OF DERIVATIVE INSTRUMENTS AEPSC is agent for and transacts on behalf of AEP subsidiaries, including the Registrant Subsidiaries. AEPEP is agent for and transacts on behalf of other AEP subsidiaries. The Registrants are exposed to certain market risks as major power producers and participants in the electricity, capacity, natural gas, coal and emission allowance markets. These risks include commodity price risks which may be subject to capacity risk, interest rate risk, credit risk and foreign currency exchange risk. These risks represent the risk of loss that may impact the Registrants due to changes in the underlying market prices or rates. Management utilizes derivative instruments to manage these risks. STRATEGIES FOR UTILIZATION OF DERIVATIVE INSTRUMENTS TO ACHIEVE OBJECTIVES Risk Management Strategies The strategy surrounding the use of derivative instruments primarily focuses on managing risk exposures, future cash flows and creating value utilizing both economic and formal hedging strategies. The risk management strategies also include the use of derivative instruments for trading purposes which focus on seizing market opportunities to create value driven by expected changes in the market prices of the commodities. To accomplish these objectives, the Registrants primarily employ risk management contracts including physical and financial forward purchase-and-sale contracts and, to a lesser extent, OTC swaps and options. Not all risk management contracts meet the definition of a derivative under the accounting guidance for “Derivatives and Hedging.” Derivative risk management contracts elected normal under the normal purchases and normal sales scope exception are not subject to the requirements of this accounting guidance. The Registrants utilize power, capacity, coal, natural gas, interest rate and, to a lesser extent, heating oil, gasoline and other commodity contracts to manage the risk associated with the energy business. The Registrants utilize interest rate derivative contracts in order to manage the interest rate exposure associated with the commodity portfolio. For disclosure purposes, such risks are grouped as “Commodity,” as these risks are related to energy risk management activities. The Registrants also utilize derivative contracts to manage interest rate risk associated with debt financing. For disclosure purposes, these risks are grouped as “Interest Rate.” The amount of risk taken is determined by the Commercial Operations, Energy Supply and Finance groups in accordance with established risk management policies as approved by the Finance Committee of the Board of Directors. The following tables represent the gross notional volume of the Registrants’ outstanding derivative contracts: Notional Volume of Derivative Instruments March 31, 2019 Primary Risk Exposure Unit of Measure AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Commodity: Power MWhs 310.4 — 43.9 25.9 7.6 7.8 2.0 Natural Gas MMBtus 80.6 — 4.0 2.3 — — 14.3 Heating Oil and Gasoline Gallons 5.4 1.1 1.0 0.5 1.3 0.5 0.6 Interest Rate USD $ 33.8 $ — $ — $ — $ — $ — $ — Interest Rate USD $ 500.0 $ — $ — $ — $ — $ — $ — Notional Volume of Derivative Instruments December 31, 2018 Primary Risk Exposure Unit of Measure AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Commodity: Power MWhs 371.1 — 66.4 40.9 7.8 15.2 4.5 Natural Gas MMBtus 87.9 — 4.0 2.3 — — 15.2 Heating Oil and Gasoline Gallons 7.4 1.5 1.4 0.7 1.8 0.7 0.8 Interest Rate USD $ 37.7 $ — $ — $ — $ — $ — $ — Interest Rate USD $ 500.0 $ — $ — $ — $ — $ — $ — Fair Value Hedging Strategies (Applies to AEP) Parent enters into interest rate derivative transactions as part of an overall strategy to manage the mix of fixed-rate and floating-rate debt. Certain interest rate derivative transactions effectively modify exposure to interest rate risk by converting a portion of fixed-rate debt to a floating-rate. Provided specific criteria are met, these interest rate derivatives may be designated as fair value hedges. Cash Flow Hedging Strategies The Registrants utilize cash flow hedges on certain derivative transactions for the purchase and sale of power (“Commodity”) in order to manage the variable price risk related to forecasted purchases and sales. Management monitors the potential impacts of commodity price changes and, where appropriate, enters into derivative transactions to protect profit margins for a portion of future electricity sales and purchases. The Registrants do not hedge all commodity price risk. The Registrants utilize a variety of interest rate derivative transactions in order to manage interest rate risk exposure. The Registrants also utilize interest rate derivative contracts to manage interest rate exposure related to future borrowings of fixed-rate debt. The Registrants do not hedge all interest rate exposure. At times, the Registrants are exposed to foreign currency exchange rate risks primarily when some fixed assets are purchased from foreign suppliers. In accordance with AEP’s risk management policy, the Registrants may utilize foreign currency derivative transactions to protect against the risk of increased cash outflows resulting from a foreign currency’s appreciation against the dollar. The Registrants do not hedge all foreign currency exposure. ACCOUNTING FOR DERIVATIVE INSTRUMENTS AND THE IMPACT ON THE FINANCIAL STATEMENTS The accounting guidance for “Derivatives and Hedging” requires recognition of all qualifying derivative instruments as either assets or liabilities on the balance sheets at fair value. The fair values of derivative instruments accounted for using MTM accounting or hedge accounting are based on exchange prices and broker quotes. If a quoted market price is not available, the estimate of fair value is based on the best information available including valuation models that estimate future energy prices based on existing market and broker quotes, supply and demand market data and assumptions. In order to determine the relevant fair values of the derivative instruments, the Registrants apply valuation adjustments for discounting, liquidity and credit quality. Credit risk is the risk that a counterparty will fail to perform on the contract or fail to pay amounts due. Liquidity risk represents the risk that imperfections in the market will cause the price to vary from estimated fair value based upon prevailing market supply and demand conditions. Since energy markets are imperfect and volatile, there are inherent risks related to the underlying assumptions in models used to fair value risk management contracts. Unforeseen events may cause reasonable price curves to differ from actual price curves throughout a contract’s term and at the time a contract settles. Consequently, there could be significant adverse or favorable effects on future net income and cash flows if market prices are not consistent with management’s estimates of current market consensus for forward prices in the current period. This is particularly true for longer term contracts. Cash flows may vary based on market conditions, margin requirements and the timing of settlement of risk management contracts. According to the accounting guidance for “Derivatives and Hedging,” the Registrants reflect the fair values of derivative instruments subject to netting agreements with the same counterparty net of related cash collateral. For certain risk management contracts, the Registrants are required to post or receive cash collateral based on third-party contractual agreements and risk profiles. AEP netted cash collateral received from third-parties against short-term and long-term risk management assets in the amounts of $9 million and $18 million as of March 31, 2019 and December 31, 2018 , respectively. AEP netted cash collateral paid to third-parties against short-term and long-term risk management liabilities in the amounts of $9 million and $4 million as of March 31, 2019 and December 31, 2018 , respectively. The netted cash collateral from third-parties against short-term and long-term risk management assets and netted cash collateral paid to third-parties against short-term and long-term risk management liabilities were immaterial for the other Registrants as of March 31, 2019 and December 31, 2018 . The following tables represent the gross fair value of the Registrants’ derivative activity on the balance sheets: AEP Fair Value of Derivative Instruments March 31, 2019 Risk Management Contracts Hedging Contracts Gross Amounts of Risk Management Assets/ Liabilities Recognized Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) Balance Sheet Location Commodity (a) Commodity (a) Interest Rate (a) (in millions) Current Risk Management Assets $ 228.3 $ 20.8 $ — $ 249.1 $ (155.2 ) $ 93.9 Long-term Risk Management Assets 279.0 7.4 — 286.4 (36.0 ) 250.4 Total Assets 507.3 28.2 — 535.5 (191.2 ) 344.3 Current Risk Management Liabilities 195.9 15.4 1.9 213.2 (149.8 ) 63.4 Long-term Risk Management Liabilities 236.6 68.6 4.4 309.6 (41.7 ) 267.9 Total Liabilities 432.5 84.0 6.3 522.8 (191.5 ) 331.3 Total MTM Derivative Contract Net Assets (Liabilities) $ 74.8 $ (55.8 ) $ (6.3 ) $ 12.7 $ 0.3 $ 13.0 Fair Value of Derivative Instruments December 31, 2018 Risk Management Contracts Hedging Contracts Gross Amounts of Risk Management Assets/ Liabilities Recognized Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) Balance Sheet Location Commodity (a) Commodity (a) Interest Rate (a) (in millions) Current Risk Management Assets $ 397.5 $ 28.5 $ — $ 426.0 $ (263.2 ) $ 162.8 Long-term Risk Management Assets 276.4 16.0 — 292.4 (38.4 ) 254.0 Total Assets 673.9 44.5 — 718.4 (301.6 ) 416.8 Current Risk Management Liabilities 293.8 13.2 2.0 309.0 (254.0 ) 55.0 Long-term Risk Management Liabilities 225.7 56.1 15.4 297.2 (33.8 ) 263.4 Total Liabilities 519.5 69.3 17.4 606.2 (287.8 ) 318.4 Total MTM Derivative Contract Net Assets (Liabilities) $ 154.4 $ (24.8 ) $ (17.4 ) $ 112.2 $ (13.8 ) $ 98.4 AEP Texas Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 0.2 — 0.2 Long-term Risk Management Liabilities — — — Total Liabilities 0.2 — 0.2 Total MTM Derivative Contract Net Liabilities $ (0.2 ) $ — $ (0.2 ) Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 0.7 (0.5 ) 0.2 Long-term Risk Management Liabilities — — — Total Liabilities 0.7 (0.5 ) 0.2 Total MTM Derivative Contract Net Assets (Liabilities) $ (0.7 ) $ 0.5 $ (0.2 ) APCo Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 40.5 $ (27.6 ) $ 12.9 Long-term Risk Management Assets 3.9 (3.6 ) 0.3 Total Assets 44.4 (31.2 ) 13.2 Current Risk Management Liabilities 33.5 (27.4 ) 6.1 Long-term Risk Management Liabilities 3.7 (3.5 ) 0.2 Total Liabilities 37.2 (30.9 ) 6.3 Total MTM Derivative Contract Net Assets (Liabilities) $ 7.2 $ (0.3 ) $ 6.9 Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 114.4 $ (57.2 ) $ 57.2 Long-term Risk Management Assets 3.1 (2.2 ) 0.9 Total Assets 117.5 (59.4 ) 58.1 Current Risk Management Liabilities 56.7 (56.3 ) 0.4 Long-term Risk Management Liabilities 2.4 (2.2 ) 0.2 Total Liabilities 59.1 (58.5 ) 0.6 Total MTM Derivative Contract Net Assets (Liabilities) $ 58.4 $ (0.9 ) $ 57.5 I&M Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 22.0 $ (17.6 ) $ 4.4 Long-term Risk Management Assets 2.3 (2.2 ) 0.1 Total Assets 24.3 (19.8 ) 4.5 Current Risk Management Liabilities 17.6 (17.3 ) 0.3 Long-term Risk Management Liabilities 2.2 (2.1 ) 0.1 Total Liabilities 19.8 (19.4 ) 0.4 Total MTM Derivative Contract Net Assets (Liabilities) $ 4.5 $ (0.4 ) $ 4.1 Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 50.4 $ (41.8 ) $ 8.6 Long-term Risk Management Assets 2.0 (1.4 ) 0.6 Total Assets 52.4 (43.2 ) 9.2 Current Risk Management Liabilities 41.1 (40.8 ) 0.3 Long-term Risk Management Liabilities 1.6 (1.5 ) 0.1 Total Liabilities 42.7 (42.3 ) 0.4 Total MTM Derivative Contract Net Assets (Liabilities) $ 9.7 $ (0.9 ) $ 8.8 OPCo Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 6.9 — 6.9 Long-term Risk Management Liabilities 99.4 — 99.4 Total Liabilities 106.3 — 106.3 Total MTM Derivative Contract Net Liabilities $ (106.3 ) $ — $ (106.3 ) Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 6.4 (0.6 ) 5.8 Long-term Risk Management Liabilities 93.8 — 93.8 Total Liabilities 100.2 (0.6 ) 99.6 Total MTM Derivative Contract Net Assets (Liabilities) $ (100.2 ) $ 0.6 $ (99.6 ) PSO Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 5.4 $ (0.4 ) $ 5.0 Long-term Risk Management Assets — — — Total Assets 5.4 (0.4 ) 5.0 Current Risk Management Liabilities 1.1 (0.4 ) 0.7 Long-term Risk Management Liabilities — — — Total Liabilities 1.1 (0.4 ) 0.7 Total MTM Derivative Contract Net Assets $ 4.3 $ — $ 4.3 Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 10.9 $ (0.5 ) $ 10.4 Long-term Risk Management Assets — — — Total Assets 10.9 (0.5 ) 10.4 Current Risk Management Liabilities 1.7 (0.7 ) 1.0 Long-term Risk Management Liabilities — — — Total Liabilities 1.7 (0.7 ) 1.0 Total MTM Derivative Contract Net Assets $ 9.2 $ 0.2 $ 9.4 SWEPCo Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 2.3 $ (0.3 ) $ 2.0 Long-term Risk Management Assets — — — Total Assets 2.3 (0.3 ) 2.0 Current Risk Management Liabilities 0.5 (0.3 ) 0.2 Long-term Risk Management Liabilities 1.9 — 1.9 Total Liabilities 2.4 (0.3 ) 2.1 Total MTM Derivative Contract Net Liabilities $ (0.1 ) $ — $ (0.1 ) Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 5.6 $ (0.8 ) $ 4.8 Long-term Risk Management Assets — — — Total Assets 5.6 (0.8 ) 4.8 Current Risk Management Liabilities 1.5 (1.1 ) 0.4 Long-term Risk Management Liabilities 2.2 — 2.2 Total Liabilities 3.7 (1.1 ) 2.6 Total MTM Derivative Contract Net Assets $ 1.9 $ 0.3 $ 2.2 (a) Derivative instruments within these categories are reported gross. These instruments are subject to master netting agreements and are presented on the balance sheets on a net basis in accordance with the accounting guidance for “Derivatives and Hedging.” (b) Amounts include counterparty netting of risk management and hedging contracts and associated cash collateral in accordance with the accounting guidance for “Derivatives and Hedging.” (c) All derivative contracts subject to a master netting arrangement or similar agreement are offset in the statement of financial position. The tables below present the Registrants’ activity of derivative risk management contracts: Amount of Gain (Loss) Recognized on Risk Management Contracts Three Months Ended March 31, 2019 Location of Gain (Loss) AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Vertically Integrated Utilities Revenues $ 0.3 $ — $ — $ — $ — $ — $ — Generation & Marketing Revenues 2.7 — — — — — — Electric Generation, Transmission and Distribution Revenues — — (0.1 ) 0.3 — — 0.1 Purchased Electricity for Resale 1.4 — — — — — — Other Operation (0.4 ) (0.1 ) (0.1 ) — (0.1 ) — — Maintenance (0.5 ) (0.1 ) — — (0.1 ) — (0.1 ) Regulatory Assets (a) (6.4 ) 0.6 (2.1 ) 0.3 (8.9 ) 0.5 (0.1 ) Regulatory Liabilities (a) (22.0 ) — (31.7 ) 6.6 — 6.2 4.7 Total Gain (Loss) on Risk Management Contracts $ (24.9 ) $ 0.4 $ (34.0 ) $ 7.2 $ (9.1 ) $ 6.7 $ 4.6 Amount of Gain (Loss) Recognized on Risk Management Contracts Three Months Ended March 31, 2018 Location of Gain (Loss) AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Vertically Integrated Utilities Revenues $ (5.5 ) $ — $ — $ — $ — $ — $ — Generation & Marketing Revenues (15.1 ) — — — — — — Electric Generation, Transmission and Distribution Revenues — — (0.3 ) (5.1 ) — — — Purchased Electricity for Resale 4.9 — 4.6 0.2 — — — Other Operation 0.3 0.1 — — 0.1 — — Maintenance 0.4 0.1 0.1 — 0.1 — — Regulatory Assets (a) 37.3 — — 6.2 31.4 — (0.3 ) Regulatory Liabilities (a) 87.0 (0.1 ) 64.1 0.2 — 12.1 (0.8 ) Total Gain (Loss) on Risk Management Contracts $ 109.3 $ 0.1 $ 68.5 $ 1.5 $ 31.6 $ 12.1 $ (1.1 ) (a) Represents realized and unrealized gains and losses subject to regulatory accounting treatment recorded as either current or noncurrent on the balance sheets. Certain qualifying derivative instruments have been designated as normal purchase or normal sale contracts, as provided in the accounting guidance for “Derivatives and Hedging.” Derivative contracts that have been designated as normal purchases or normal sales under that accounting guidance are not subject to MTM accounting treatment and are recognized on the statements of income on an accrual basis. The accounting for the changes in the fair value of a derivative instrument depends on whether it qualifies for and has been designated as part of a hedging relationship and further, on the type of hedging relationship. Depending on the exposure, management designates a hedging instrument as a fair value hedge or a cash flow hedge. For contracts that have not been designated as part of a hedging relationship, the accounting for changes in fair value depends on whether the derivative instrument is held for trading purposes. Unrealized and realized gains and losses on derivative instruments held for trading purposes are included in revenues on a net basis on the statements of income. Unrealized and realized gains and losses on derivative instruments not held for trading purposes are included in revenues or expenses on the statements of income depending on the relevant facts and circumstances. Certain derivatives that economically hedge future commodity risk are recorded in the same expense line item on the statements of income as that of the associated risk. However, unrealized and some realized gains and losses in regulated jurisdictions for both trading and non-trading derivative instruments are recorded as regulatory assets (for losses) or regulatory liabilities (for gains) in accordance with the accounting guidance for “Regulated Operations.” Accounting for Fair Value Hedging Strategies (Applies to AEP) For fair value hedges (i.e. hedging the exposure to changes in the fair value of an asset, liability or an identified portion thereof attributable to a particular risk), the gain or loss on the derivative instrument as well as the offsetting gain or loss on the hedged item associated with the hedged risk impacts net income during the period of change. AEP records realized and unrealized gains or losses on interest rate swaps that are designated and qualify for fair value hedge accounting treatment and any offsetting changes in the fair value of the debt being hedged in Interest Expense on the statements of income. The following table shows the impacts recognized on the balance sheets related to the hedged items in fair value hedging relationships: Carrying Amount of the Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) March 31, 2019 December 31, 2018 March 31, 2019 December 31, 2018 (in millions) Long-term Debt (a) $ (489.6 ) $ (478.3 ) $ 6.3 $ 17.4 (a) Amounts included on the balance sheets within Long-term Debt Due within One Year and Long-term Debt, respectively. The pretax effects of fair value hedge accounting on income were as follows: Three Months Ended March 31, 2019 2018 (in millions) Gain (Loss) on Interest Rate Contracts: Gain (Loss) on Fair Value Hedging Instruments (a) $ 11.1 $ (14.5 ) Gain (Loss) on Fair Value Portion of Long-term Debt (a) (11.1 ) 14.5 (a) Gain (Loss) is included in Interest Expense on the statements of income. Accounting for Cash Flow Hedging Strategies For cash flow hedges (i.e. hedging the exposure to variability in expected future cash flows that is attributable to a particular risk), the Registrants initially report the gain or loss on the derivative instrument as a component of Accumulated Other Comprehensive Income (Loss) on the balance sheets until the period the hedged item affects net income. Realized gains and losses on derivative contracts for the purchase and sale of power designated as cash flow hedges are included in Total Revenues or Purchased Electricity for Resale on the statements of income or in Regulatory Assets or Regulatory Liabilities on the balance sheets, depending on the specific nature of the risk being hedged. During the three months ended March 31, 2019 and 2018 , AEP applied cash flow hedging to outstanding power derivatives. During the three months ended March 31, 2019 and 2018 , the Registrant Subsidiaries did not apply cash flow hedging to outstanding power derivatives. The Registrants reclassify gains and losses on interest rate derivative hedges related to debt financings from Accumulated Other Comprehensive Income (Loss) on the balance sheets into Interest Expense on the statements of income in those periods in which hedged interest payments occur. During the three months ended March 31, 2019 and 2018 , the Registrants did not apply cash flow hedging to outstanding interest rate derivatives. The accumulated gains or losses related to foreign currency hedges are reclassified from Accumulated Other Comprehensive Income (Loss) on the balance sheets into Depreciation and Amortization expense on the statements of income over the depreciable lives of the fixed assets designated as the hedged items in qualifying foreign currency hedging relationships. During the three months ended March 31, 2019 and 2018 , the Registrants did not apply cash flow hedging to any outstanding foreign currency derivatives. For details on effective cash flow hedges included in Accumulated Other Comprehensive Income (Loss) on the balance sheets and the reasons for changes in cash flow hedges, see Note 3 - Comprehensive Income. Cash flow hedges included in Accumulated Other Comprehensive Income (Loss) on the balance sheets were: Impact of Cash Flow Hedges on AEP’s Balance Sheets March 31, 2019 December 31, 2018 Commodity Interest Rate Commodity Interest Rate (in millions) AOCI Gain (Loss) Net of Tax (52.1 ) (12.4 ) (23.0 ) (12.6 ) Portion Expected to be Reclassed to Net Income During the Next Twelve Months 1.6 (1.5 ) 10.4 (1.1 ) As of March 31, 2019 the maximum length of time that AEP is hedging its exposure to variability in future cash flows related to forecasted transactions is 177 months. Impact of Cash Flow Hedges on the Registrant Subsidiaries’ Balance Sheets March 31, 2019 December 31, 2018 Interest Rate Company AOCI Gain (Loss) Net of Tax Expected to be Reclassed to Net Income During the Next Twelve Months AOCI Gain (Loss) Net of Tax Expected to be Reclassed to Net Income During the Next Twelve Months (in millions) AEP Texas $ (4.1 ) $ (1.1 ) $ (4.4 ) $ (1.1 ) APCo 1.6 0.9 1.8 0.9 I&M (11.1 ) (1.6 ) (11.5 ) (1.6 ) OPCo 0.7 0.6 1.0 1.0 PSO 1.9 1.0 2.1 1.0 SWEPCo (2.9 ) (1.5 ) (3.3 ) (1.5 ) The actual amounts reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income can differ from the estimate above due to market price changes. Credit Risk Management mitigates credit risk in wholesale marketing and trading activities by assessing the creditworthiness of potential counterparties before entering into transactions with them and continuing to evaluate their creditworthiness on an ongoing basis. Management uses credit agency ratings and current market-based qualitative and quantitative data as well as financial statements to assess the financial health of counterparties on an ongoing basis. Master agreements are typically used to facilitate the netting of cash flows associated with a single counterparty and may include collateral requirements. Collateral requirements in the form of cash, letters of credit and parental/affiliate guarantees may be obtained as security from counterparties in order to mitigate credit risk. Some master agreements include margining, which requires a counterparty to post cash or letters of credit in the event exposure exceeds the established threshold. The threshold represents an unsecured credit limit which may be supported by a parental/affiliate guaranty, as determined in accordance with AEP’s credit policy. In addition, master agreements allow for termination and liquidation of all positions in the event of a default including a failure or inability to post collateral when required. Collateral Triggering Events Credit Downgrade Triggers (Applies to AEP, APCo, I&M, PSO and SWEPCo) A limited number of derivative contracts include collateral triggering events, which include a requirement to maintain certain credit ratings. On an ongoing basis, AEP’s risk management organization assesses the appropriateness of these collateral triggering events in contracts. The Registrants have not experienced a downgrade below a specified credit rating threshold that would require the posting of additional collateral. The Registrants had no derivative contracts with collateral triggering events in a net liability position as of March 31, 2019 and December 31, 2018 , respectively. Cross-Default Triggers (Applies to AEP, APCo, I&M and SWEPCo) In addition, a majority of non-exchange-traded commodity contracts contain cross-default provisions that, if triggered, would permit the counterparty to declare a default and require settlement of the outstanding payable. These cross-default provisions could be triggered if there was a non-performance event by Parent or the obligor under outstanding debt or a third-party obligation that is $50 million or greater. On an ongoing basis, AEP’s risk management organization assesses the appropriateness of these cross-default provisions in the contracts. The following tables represent: (a) the fair value of these derivative liabilities subject to cross-default provisions prior to consideration of contractual netting arrangements, (b) the amount that the exposure has been reduced by cash collateral posted and (c) if a cross-default provision would have been triggered, the settlement amount that would be required after considering contractual netting arrangements: March 31, 2019 Liabilities for Additional Contracts with Cross Settlement Default Provisions Liability if Cross Prior to Contractual Amount of Cash Default Provision Company Netting Arrangements Collateral Posted is Triggered (in millions) AEP $ 219.2 $ 3.8 $ 189.0 APCo 1.4 — 0.1 I&M 0.8 — 0.1 SWEPCo 2.0 — 1.9 December 31, 2018 Liabilities for Additional Contracts with Cross Settlement Default Provisions Liability if Cross Prior to Contractual Amount of Cash Default Provision Company Netting Arrangements Collateral Posted is Triggered (in millions) AEP $ 225.5 $ 1.8 $ 181.0 APCo 0.9 — — I&M 0.5 — — SWEPCo 2.3 — 2.3

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Measurements	FAIR VALUE MEASUREMENTS The disclosures in this note apply to all Registrants except AEPTCo unless indicated otherwise. Fair Value Hierarchy and Valuation Techniques The accounting guidance for “Fair Value Measurements and Disclosures” establishes a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). Where observable inputs are available for substantially the full term of the asset or liability, the instrument is categorized in Level 2. When quoted market prices are not available, pricing may be completed using comparable securities, dealer values, operating data and general market conditions to determine fair value. Valuation models utilize various inputs such as commodity, interest rate and, to a lesser degree, volatility and credit that include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in inactive markets, market corroborated inputs (i.e. inputs derived principally from, or correlated to, observable market data) and other observable inputs for the asset or liability. For commercial activities, exchange-traded derivatives, namely futures contracts, are generally fair valued based on unadjusted quoted prices in active markets and are classified as Level 1. Level 2 inputs primarily consist of OTC broker quotes in moderately active or less active markets, as well as exchange-traded derivatives where there is insufficient market liquidity to warrant inclusion in Level 1. Management verifies price curves using these broker quotes and classifies these fair values within Level 2 when substantially all of the fair value can be corroborated. Management typically obtains multiple broker quotes, which are nonbinding in nature but are based on recent trades in the marketplace. When multiple broker quotes are obtained, the quoted bid and ask prices are averaged. In certain circumstances, a broker quote may be discarded if it is a clear outlier. Management uses a historical correlation analysis between the broker quoted location and the illiquid locations. If the points are highly correlated, these locations are included within Level 2 as well. Certain OTC and bilaterally executed derivative instruments are executed in less active markets with a lower availability of pricing information. Illiquid transactions, complex structured transactions, FTRs and counterparty credit risk may require nonmarket-based inputs. Some of these inputs may be internally developed or extrapolated and utilized to estimate fair value. When such inputs have a significant impact on the measurement of fair value, the instrument is categorized as Level 3. The main driver of contracts being classified as Level 3 is the inability to substantiate energy price curves in the market. A portion of the Level 3 instruments have been economically hedged which limits potential earnings volatility. AEP utilizes its trustee’s external pricing service to estimate the fair value of the underlying investments held in the nuclear trusts. AEP’s investment managers review and validate the prices utilized by the trustee to determine fair value. AEP’s management performs its own valuation testing to verify the fair values of the securities. AEP receives audit reports of the trustee’s operating controls and valuation processes. The trustee uses multiple pricing vendors for the assets held in the trusts. Assets in the nuclear trusts, cash and cash equivalents, other temporary investments and restricted cash for securitized funding are classified using the following methods. Equities are classified as Level 1 holdings if they are actively traded on exchanges. Items classified as Level 1 are investments in money market funds, fixed income and equity mutual funds and equity securities. They are valued based on observable inputs, primarily unadjusted quoted prices in active markets for identical assets. Items classified as Level 2 are primarily investments in individual fixed income securities. Fixed income securities generally do not trade on exchanges and do not have an official closing price but their valuation inputs are based on observable market data. Pricing vendors calculate bond valuations using financial models and matrices. The models use observable inputs including yields on benchmark securities, quotes by securities brokers, rating agency actions, discounts or premiums on securities compared to par prices, changes in yields for U.S. Treasury securities, corporate actions by bond issuers, prepayment schedules and histories, economic events and, for certain securities, adjustments to yields to reflect changes in the rate of inflation. Other securities with model-derived valuation inputs that are observable are also classified as Level 2 investments. Investments with unobservable valuation inputs are classified as Level 3 investments. Fair Value Measurements of Long-term Debt (Applies to all Registrants) The fair values of Long-term Debt are based on quoted market prices, without credit enhancements, for the same or similar issues and the current interest rates offered for instruments with similar maturities classified as Level 2 measurement inputs. These instruments are not marked-to-market. The estimates presented are not necessarily indicative of the amounts that could be realized in a current market exchange. The fair value of AEP’s Equity Units (Level 1) are valued based on publicly traded securities issued by AEP. The book values and fair values of Long-term Debt are summarized in the following table: March 31, 2019 December 31, 2018 Company Book Value Fair Value Book Value Fair Value (in millions) AEP (a) $ 24,426.7 $ 26,225.6 $ 23,346.7 $ 24,093.9 AEP Texas 3,778.3 3,973.4 3,881.3 3,964.6 AEPTCo 2,823.4 2,949.6 2,823.0 2,782.4 APCo 4,444.0 5,040.6 4,062.6 4,473.3 I&M 3,011.4 3,201.8 3,035.4 3,070.2 OPCo 1,693.6 1,989.2 1,716.6 1,919.7 PSO 1,386.2 1,503.6 1,287.0 1,361.9 SWEPCo 2,659.1 2,763.0 2,713.4 2,670.2 (a) The fair value amount includes debt related to AEP’s Equity Units issued in March 2019 and has a fair value of $828 million as of March 31, 2019 . See “Equity Units” section of Note 13 for additional information. Fair Value Measurements of Other Temporary Investments (Applies to AEP) Other Temporary Investments include marketable securities that management intends to hold for less than one year and investments by AEP’s protected cell of EIS. The following is a summary of Other Temporary Investments: March 31, 2019 Other Temporary Investments Cost Gross Gains Gross Losses Fair Value (in millions) Restricted Cash and Other Cash Deposits (a) $ 159.6 $ — $ — $ 159.6 Fixed Income Securities – Mutual Funds (b) 107.2 — (1.3 ) 105.9 Equity Securities – Mutual Funds 22.5 16.3 — 38.8 Total Other Temporary Investments $ 289.3 $ 16.3 $ (1.3 ) $ 304.3 December 31, 2018 Other Temporary Investments Cost Gross Gains Gross Losses Fair Value (in millions) Restricted Cash and Other Cash Deposits (a) $ 230.6 $ — $ — $ 230.6 Fixed Income Securities – Mutual Funds (b) 106.6 — (2.3 ) 104.3 Equity Securities – Mutual Funds 17.8 16.4 — 34.2 Total Other Temporary Investments $ 355.0 $ 16.4 $ (2.3 ) $ 369.1 (a) Primarily represents amounts held for the repayment of debt. (b) Primarily short and intermediate maturities which may be sold and do not contain maturity dates. The following table provides the activity for fixed income and equity securities within Other Temporary Investments: Three Months Ended March 31, 2019 2018 (in millions) Proceeds from Investment Sales $ — $ — Purchases of Investments 0.1 0.6 Gross Realized Gains on Investment Sales — — Gross Realized Losses on Investment Sales — — For details of the reasons for changes in Securities Available for Sale included in Accumulated Other Comprehensive Income (Loss) for the three months ended March 31, 2018 , see Note 3 - Comprehensive Income. Fair Value Measurements of Trust Assets for Decommissioning and SNF Disposal (Applies to AEP and I&M) Nuclear decommissioning and SNF trust funds represent funds that regulatory commissions allow I&M to collect through rates to fund future decommissioning and SNF disposal liabilities. By rules or orders, the IURC, the MPSC and the FERC established investment limitations and general risk management guidelines. In general, limitations include: • Acceptable investments (rated investment grade or above when purchased). • Maximum percentage invested in a specific type of investment. • Prohibition of investment in obligations of AEP, I&M or their affiliates. • Withdrawals permitted only for payment of decommissioning costs and trust expenses. I&M maintains trust funds for each regulatory jurisdiction. Regulatory approval is required to withdraw decommissioning funds. These funds are managed by external investment managers who must comply with the guidelines and rules of the applicable regulatory authorities. The trust assets are invested to optimize the net of tax earnings of the trust giving consideration to liquidity, risk, diversification and other prudent investment objectives. I&M records securities held in these trust funds in Spent Nuclear Fuel and Decommissioning Trusts on its balance sheets. I&M records these securities at fair value. I&M classifies securities in the trust funds as available-for-sale due to their long-term purpose. With the adoption of ASU 2016-01, effective January 2018, available-for-sale classification only applies to investment in debt securities. Additionally, the adoption of ASU 2016-01 required changes in fair value of equity securities to be recognized in earnings. However, due to the regulatory treatment described below, this is not applicable for I&M’s trust fund securities. Other-than-temporary impairments for investments in debt securities are considered realized losses as a result of securities being managed by an external investment management firm. The external investment management firm makes specific investment decisions regarding the debt and equity investments held in these trusts and generally intends to sell debt securities in an unrealized loss position as part of a tax optimization strategy. Impairments reduce the cost basis of the securities which will affect any future unrealized gain or realized gain or loss due to the adjusted cost of investment. I&M records unrealized gains, unrealized losses and other-than-temporary impairments from securities in these trust funds as adjustments to the regulatory liability account for the nuclear decommissioning trust funds and to regulatory assets or liabilities for the SNF disposal trust funds in accordance with their treatment in rates. Consequently, changes in fair value of trust assets do not affect earnings or AOCI. The following is a summary of nuclear trust fund investments: March 31, 2019 December 31, 2018 Fair Value Gross Unrealized Gains Other-Than-Temporary Impairments Fair Value Gross Unrealized Gains Other-Than-Temporary Impairments (in millions) Cash and Cash Equivalents $ 17.4 $ — $ — $ 22.5 $ — $ — Fixed Income Securities: United States Government 1,015.6 44.0 (6.7 ) 996.1 26.7 (7.1 ) Corporate Debt 54.2 2.9 (1.8 ) 52.4 1.1 (1.9 ) State and Local Government 8.7 0.7 (0.2 ) 8.6 0.6 (0.2 ) Subtotal Fixed Income Securities 1,078.5 47.6 (8.7 ) 1,057.1 28.4 (9.2 ) Equity Securities – Domestic (a) 1,588.1 945.6 — 1,395.3 766.3 — Spent Nuclear Fuel and Decommissioning Trusts $ 2,684.0 $ 993.2 $ (8.7 ) $ 2,474.9 $ 794.7 $ (9.2 ) (a) Amount reported as Gross Unrealized Gains includes unrealized gains of $955 million and $784 million and unrealized losses of $9 million and $18 million as of March 31, 2019 and December 31, 2018 , respectively. AEP adopted ASU 2016-01 during the first quarter of 2018 by means of a modified retrospective approach. Due to the adoption of the ASU, Other-Than-Temporary Impairments are no longer applicable to Equity Securities with readily determinable fair values. The following table provides the securities activity within the decommissioning and SNF trusts: Three Months Ended March 31, 2019 2018 (in millions) Proceeds from Investment Sales $ 111.9 $ 508.6 Purchases of Investments 130.3 525.3 Gross Realized Gains on Investment Sales 12.3 12.0 Gross Realized Losses on Investment Sales 13.8 10.9 The base cost of fixed income securities was $1 billion and $1 billion as of March 31, 2019 and December 31, 2018 , respectively. The base cost of equity securities was $643 million and $629 million as of March 31, 2019 and December 31, 2018 , respectively. The fair value of fixed income securities held in the nuclear trust funds, summarized by contractual maturities, as of March 31, 2019 was as follows: Fair Value of Fixed Income Securities (in millions) Within 1 year $ 356.4 After 1 year through 5 years 375.4 After 5 years through 10 years 172.8 After 10 years 173.9 Total $ 1,078.5 Fair Value Measurements of Financial Assets and Liabilities The following tables set forth, by level within the fair value hierarchy, the Registrants’ financial assets and liabilities that were accounted for at fair value on a recurring basis. As required by the accounting guidance for “Fair Value Measurements and Disclosures,” financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Management’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels. There have not been any significant changes in management’s valuation techniques. AEP Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Other Temporary Investments Restricted Cash and Other Cash Deposits (a) $ 147.1 $ — $ — $ 12.5 $ 159.6 Fixed Income Securities – Mutual Funds 105.9 — — — 105.9 Equity Securities – Mutual Funds (b) 38.8 — — — 38.8 Total Other Temporary Investments 291.8 — — 12.5 304.3 Risk Management Assets Risk Management Commodity Contracts (c) (d) 2.5 200.4 276.6 (155.4 ) 324.1 Cash Flow Hedges: Commodity Hedges (c) — 14.8 5.5 (0.1 ) 20.2 Total Risk Management Assets 2.5 215.2 282.1 (155.5 ) 344.3 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 9.3 — — 8.1 17.4 Fixed Income Securities: United States Government — 1,015.6 — — 1,015.6 Corporate Debt — 54.2 — — 54.2 State and Local Government — 8.7 — — 8.7 Subtotal Fixed Income Securities — 1,078.5 — — 1,078.5 Equity Securities – Domestic (b) 1,588.1 — — — 1,588.1 Total Spent Nuclear Fuel and Decommissioning Trusts 1,597.4 1,078.5 — 8.1 2,684.0 Total Assets $ 1,891.7 $ 1,293.7 $ 282.1 $ (134.9 ) $ 3,332.6 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (d) $ 2.7 $ 204.8 $ 197.2 $ (155.7 ) $ 249.0 Cash Flow Hedges: Commodity Hedges (c) — 29.3 46.8 (0.1 ) 76.0 Fair Value Hedges — 6.3 — — 6.3 Total Risk Management Liabilities $ 2.7 $ 240.4 $ 244.0 $ (155.8 ) $ 331.3 AEP Assets and Liabilities Measured at Fair Value on a Recurring Basis December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Other Temporary Investments Restricted Cash and Other Cash Deposits (a) $ 221.5 $ — $ — $ 9.1 $ 230.6 Fixed Income Securities – Mutual Funds 104.3 — — — 104.3 Equity Securities – Mutual Funds (b) 34.2 — — — 34.2 Total Other Temporary Investments 360.0 — — 9.1 369.1 Risk Management Assets Risk Management Commodity Contracts (c) (f) 3.8 326.5 340.9 (288.5 ) 382.7 Cash Flow Hedges: Commodity Hedges (c) — 24.1 12.7 (2.7 ) 34.1 Total Risk Management Assets 3.8 350.6 353.6 (291.2 ) 416.8 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 12.3 — — 10.2 22.5 Fixed Income Securities: United States Government — 996.1 — — 996.1 Corporate Debt — 52.4 — — 52.4 State and Local Government — 8.6 — — 8.6 Subtotal Fixed Income Securities — 1,057.1 — — 1,057.1 Equity Securities – Domestic (b) 1,395.3 — — — 1,395.3 Total Spent Nuclear Fuel and Decommissioning Trusts 1,407.6 1,057.1 — 10.2 2,474.9 Total Assets $ 1,771.4 $ 1,407.7 $ 353.6 $ (271.9 ) $ 3,260.8 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (f) $ 4.2 $ 327.0 $ 185.6 $ (274.7 ) $ 242.1 Cash Flow Hedges: Commodity Hedges (c) — 24.8 36.8 (2.7 ) 58.9 Fair Value Hedges — 17.4 — — 17.4 Total Risk Management Liabilities $ 4.2 $ 369.2 $ 222.4 $ (277.4 ) $ 318.4 AEP Texas Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 100.6 $ — $ — $ — $ 100.6 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) $ — $ 0.2 $ — $ — $ 0.2 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 156.7 $ — $ — $ — $ 156.7 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) $ — $ 0.7 $ — $ (0.5 ) $ 0.2 APCo Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 18.3 $ — $ — $ — $ 18.3 Risk Management Assets Risk Management Commodity Contracts (c) (g) 0.2 26.8 13.4 (27.2 ) 13.2 Total Assets $ 18.5 $ 26.8 $ 13.4 $ (27.2 ) $ 31.5 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.2 $ 27.0 $ 6.0 $ (26.9 ) $ 6.3 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 25.6 $ — $ — $ — $ 25.6 Risk Management Assets Risk Management Commodity Contracts (c) (g) 0.1 59.1 58.3 (59.4 ) 58.1 Total Assets $ 25.7 $ 59.1 $ 58.3 $ (59.4 ) $ 83.7 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.2 $ 58.4 $ 0.5 $ (58.5 ) $ 0.6 I&M Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ 16.7 $ 5.2 $ (17.4 ) $ 4.5 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 9.3 — — 8.1 17.4 Fixed Income Securities: United States Government — 1,015.6 — — 1,015.6 Corporate Debt — 54.2 — — 54.2 State and Local Government — 8.7 — — 8.7 Subtotal Fixed Income Securities — 1,078.5 — — 1,078.5 Equity Securities - Domestic (b) 1,588.1 — — — 1,588.1 Total Spent Nuclear Fuel and Decommissioning Trusts 1,597.4 1,078.5 — 8.1 2,684.0 Total Assets $ 1,597.4 $ 1,095.2 $ 5.2 $ (9.3 ) $ 2,688.5 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.1 $ 16.5 $ 0.8 $ (17.0 ) $ 0.4 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ 42.1 $ 10.3 $ (43.2 ) $ 9.2 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 12.3 — — 10.2 22.5 Fixed Income Securities: United States Government — 996.1 — — 996.1 Corporate Debt — 52.4 — — 52.4 State and Local Government — 8.6 — — 8.6 Subtotal Fixed Income Securities — 1,057.1 — — 1,057.1 Equity Securities - Domestic (b) 1,395.3 — — — 1,395.3 Total Spent Nuclear Fuel and Decommissioning Trusts 1,407.6 1,057.1 — 10.2 2,474.9 Total Assets $ 1,407.6 $ 1,099.2 $ 10.3 $ (33.0 ) $ 2,484.1 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.1 $ 41.2 $ 1.4 $ (42.3 ) $ 0.4 OPCo Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 16.5 $ — $ — $ — $ 16.5 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.2 $ 106.1 $ — $ 106.3 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 27.6 $ — $ — $ — $ 27.6 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.8 $ 99.4 $ (0.6 ) $ 99.6 PSO Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 5.4 $ (0.4 ) $ 5.0 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.1 $ 1.0 $ (0.4 ) $ 0.7 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 10.8 $ (0.4 ) $ 10.4 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.3 $ 1.3 $ (0.6 ) $ 1.0 SWEPCo Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 2.3 $ (0.3 ) $ 2.0 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.1 $ 2.3 $ (0.3 ) $ 2.1 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 5.6 $ (0.8 ) $ 4.8 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.4 $ 3.3 $ (1.1 ) $ 2.6 (a) Amounts in “Other’’ column primarily represent cash deposits in bank accounts with financial institutions or third-parties. Level 1 and Level 2 amounts primarily represent investments in money market funds. (b) Amounts represent publicly traded equity securities and equity-based mutual funds. (c) Amounts in “Other’’ column primarily represent counterparty netting of risk management and hedging contracts and associated cash collateral under the accounting guidance for “Derivatives and Hedging.” (d) The March 31, 2019 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(7) million in 2019, $2 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $27 million in 2019, $42 million in periods 2020-2022, $23 million in periods 2023-2024 and $(13) million in periods 2025-2032. Risk management commodity contracts are substantially comprised of power contracts. (e) Amounts in “Other’’ column primarily represent accrued interest receivables from financial institutions. Level 1 amounts primarily represent investments in money market funds. (f) The December 31, 2018 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(4) million in 2019, $1 million in periods 2020-2022, $1 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $108 million in 2019, $37 million in periods 2020-2022, $23 million in periods 2023-2024 and $(12) million in periods 2025-2032. Risk management commodity contracts are substantially comprised of power contracts. (g) Substantially comprised of power contracts for the Registrant Subsidiaries. There were no transfers between Level 1 and Level 2 during the three months ended March 31, 2019 and 2018 . The following tables set forth a reconciliation of changes in the fair value of net trading derivatives classified as Level 3 in the fair value hierarchy: Three Months Ended March 31, 2019 AEP APCo I&M OPCo PSO SWEPCo (in millions) Balance as of December 31, 2018 $ 131.2 $ 57.8 $ 8.9 $ (99.4 ) $ 9.5 $ 2.3 Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) (a) (b) (23.0 ) (29.0 ) — (0.4 ) 6.8 3.3 Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date (a) 8.5 — — — — — Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income (15.8 ) — — — — — Settlements (54.5 ) (17.8 ) (5.1 ) 1.8 (13.0 ) (7.3 ) Transfers into Level 3 (c) (d) 0.1 — — — — — Transfers out of Level 3 (d) (1.2 ) (0.7 ) (0.4 ) — — — Changes in Fair Value Allocated to Regulated Jurisdictions (e) (7.2 ) (2.9 ) 1.0 (8.1 ) 1.1 1.7 Balance as of March 31, 2019 $ 38.1 $ 7.4 $ 4.4 $ (106.1 ) $ 4.4 $ — Three Months Ended March 31, 2018 AEP APCo I&M OPCo PSO SWEPCo (in millions) Balance as of December 31, 2017 $ 40.3 $ 24.7 $ 7.6 $ (132.4 ) $ 6.2 $ 5.9 Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) (a) (b) 97.3 68.1 3.0 0.3 11.4 0.6 Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date (a) 2.0 — — — — — Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income 17.9 — — — — — Settlements (129.8 ) (85.4 ) (7.4 ) 1.1 (16.1 ) (3.9 ) Transfers into Level 3 (c) (d) 2.1 — — — — — Transfers out of Level 3 (d) (2.0 ) — (0.3 ) — — — Changes in Fair Value Allocated to Regulated Jurisdictions (e) 34.2 1.7 — 32.5 1.3 (1.7 ) Balance as of March 31, 2018 $ 62.0 $ 9.1 $ 2.9 $ (98.5 ) $ 2.8 $ 0.9 (a) Included in revenues on the statements of income. (b) Represents the change in fair value between the beginning of the reporting period and the settlement of the risk management commodity contract. (c) Represents existing assets or liabilities that were previously categorized as Level 2. (d) Transfers are recognized based on their value at the beginning of the reporting period that the transfer occurred. (e) Relates to the net gains (losses) of those contracts that are not reflected on the statements of income. These net gains (losses) are recorded as regulatory assets/liabilities or accounts payable. The following tables quantify the significant unobservable inputs used in developing the fair value of Level 3 positions: Significant Unobservable Inputs March 31, 2019 AEP Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Energy Contracts $ 256.7 $ 229.0 Discounted Cash Flow Forward Market Price (a) $ (0.05 ) $ 165.64 $ 32.60 Natural Gas Contracts — 2.0 Discounted Cash Flow Forward Market Price (b) 2.27 2.87 2.48 FTRs 25.4 13.0 Discounted Cash Flow Forward Market Price (a) (8.34 ) 10.30 (0.02 ) Total $ 282.1 $ 244.0 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Energy Contracts $ 257.1 $ 212.5 Discounted Cash Flow Forward Market Price (a) $ (0.05 ) $ 176.57 $ 33.07 Natural Gas Contracts — 2.5 Discounted Cash Flow Forward Market Price (b) 2.18 3.54 2.47 FTRs 96.5 7.4 Discounted Cash Flow Forward Market Price (a) (11.68 ) 17.79 1.09 Total $ 353.6 $ 222.4 Significant Unobservable Inputs March 31, 2019 APCo Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 3.6 $ 0.4 Discounted Cash Flow Forward Market Price $ 17.40 $ 49.25 $ 34.91 FTRs 9.8 5.6 Discounted Cash Flow Forward Market Price (0.06 ) 2.44 0.61 Total $ 13.4 $ 6.0 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 2.4 $ 0.5 Discounted Cash Flow Forward Market Price $ 16.82 $ 62.65 $ 37.00 FTRs 55.9 — Discounted Cash Flow Forward Market Price 0.10 15.16 3.27 Total $ 58.3 $ 0.5 Significant Unobservable Inputs March 31, 2019 I&M Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 1.9 $ 0.3 Discounted Cash Flow Forward Market Price $ 17.40 $ 49.25 $ 34.91 FTRs 3.3 0.5 Discounted Cash Flow Forward Market Price (0.10 ) 2.02 0.86 Total $ 5.2 $ 0.8 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 1.4 $ 0.9 Discounted Cash Flow Forward Market Price $ 16.82 $ 62.65 $ 37.00 FTRs 8.9 0.5 Discounted Cash Flow Forward Market Price (2.11 ) 6.21 1.06 Total $ 10.3 $ 1.4 Significant Unobservable Inputs March 31, 2019 OPCo Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ — $ 106.1 Discounted Cash Flow Forward Market Price $ 25.35 $ 66.99 $ 43.29 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ — $ 99.4 Discounted Cash Flow Forward Market Price $ 26.29 $ 62.74 $ 42.50 Significant Unobservable Inputs March 31, 2019 PSO Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) FTRs $ 5.4 $ 1.0 Discounted Cash Flow Forward Market Price $ (8.34 ) $ 10.30 $ (1.09 ) December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) FTRs $ 10.8 $ 1.3 Discounted Cash Flow Forward Market Price $ (11.68 ) $ 10.30 $ (1.40 ) Significant Unobservable Inputs March 31, 2019 SWEPCo Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Natural Gas Contracts $ — $ 2.0 Discounted Cash Flow Forward Market Price (b) $ 2.27 $ 2.87 $ 2.48 FTRs 2.3 0.3 Discounted Cash Flow Forward Market Price (a) (8.34 ) 10.30 (1.09 ) Total $ 2.3 $ 2.3 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Natural Gas Contracts $ — $ 2.5 Discounted Cash Flow Forward Market Price (b) $ 2.18 $ 3.54 $ 2.47 FTRs 5.6 0.8 Discounted Cash Flow Forward Market Price (a) (11.68 ) 10.30 (1.40 ) Total $ 5.6 $ 3.3 (a) Represents market prices in dollars per MWh. (b) Represents market prices in dollars per MMBtu. The following table provides sensitivity of fair value measurements to increases (decreases) in significant unobservable inputs related to Energy Contracts, Natural Gas Contracts and FTRs for the Registrants as of March 31, 2019 and December 31, 2018 : Sensitivity of Fair Value Measurements Significant Unobservable Input Position Change in Input Impact on Fair Value Measurement Forward Market Price Buy Increase (Decrease) Higher (Lower) Forward Market Price Sell Increase (Decrease) Lower (Higher)

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2019
Income Taxes	INCOME TAXES The disclosures in this note apply to all Registrants unless indicated otherwise. Status of Tax Reform Regulatory Proceedings For AEP’s various regulatory jurisdictions where the regulatory effects of Tax Reform proceedings have not been fully resolved, the table below summarizes the current status. See Note 4 - Rate Matters for additional information. Registrant (Jurisdiction) Change in Tax Rate Excess ADIT Subject to Normalization Requirements Excess ADIT Not Subject to Normalization Requirements AEP Texas (Texas-Distribution) Order Issued Order Issued Order Issued – Partial (a) AEP Texas (Texas-Transmission) Order Issued To be addressed in a later filing To be addressed in a later filing I&M (Michigan) Order Issued Case Pending Case Pending SWEPCo (Louisiana) Case Pending – Rates Implemented (b) Case Pending – Rates Implemented (b) Case Pending – Rates Implemented (b) SWEPCo (Texas) Order Issued To be addressed in a later filing To be addressed in a later filing PJM FERC Transmission Settlement Approved (c) Settlement Approved (c) Settlement Approved (c) SPP FERC Transmission Settlement Pending Settlement Pending Settlement Pending (a) A portion of the Excess ADIT that is not subject to rate normalization requirements is to be addressed in a later filing. (b) Rates have been implemented through a filed formula rate plan that is subject to true-up and final commission approval. (c) An ALJ has approved a settlement. The settlement is subject to final FERC ruling. Effective Tax Rates (ETR) The Registrants’ interim ETR reflect the estimated annual ETR for 2019 and 2018, adjusted for tax expense associated with certain discrete items. The interim ETR differ from the federal statutory tax rate of 21% primarily due to increased amortization of Excess ADIT, tax credits and other book/tax differences which are accounted for on a flow-through basis. The Registrants include the amortization of Excess ADIT not subject to normalization requirements in the annual estimated ETR when regulatory proceedings instruct the Registrants to provide the benefits of Tax Reform to customers over multiple interim periods. Certain regulatory proceedings instruct the Registrants to provide the benefits of Tax Reform to customers in a single period (e.g. by applying the Excess ADIT not subject to normalization requirements against an existing regulatory asset balance) and in these circumstances, the Registrants recognize the tax benefit discretely in the period recorded. The annual amount of Excess ADIT approved by the Registrant’s regulatory commissions may not impact the ETR ratably during each interim period due to the variability of pretax book income between interim periods and the application of an annual estimated ETR. The ETR for each of the Registrants are included in the following table. Significant variances in the ETR are described below. Three Months Ended Company 2019 2018 AEP 7.2 % 18.3 % AEP Texas 10.4 % 16.3 % AEPTCo 20.9 % 20.7 % APCo (22.0 )% 18.2 % I&M (2.8 )% 16.2 % OPCo 13.4 % 20.5 % PSO 0.6 % 16.3 % SWEPCo 2.4 % 18.4 % AEP Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $66 million of increased amortization of Excess ADIT not subject to normalization requirements which impacted the ETR by (10.8)% . AEP Texas Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $1 million of increased amortization of Excess ADIT not subject to normalization requirements and an increase in parent company loss benefit which impacted the ETR by (3.9)% and (2.2)% , respectively. Amortization of Excess ADIT not subject to normalization requirements for the three months ended March 31, 2019 reflects Tax Reform elements of a Stipulation and Settlement agreement approved by the PUCT in August 2018. AEPTCo Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The increase in the ETR is primarily due to the decrease in favorable book/tax differences accounted for on a flow-through basis. APCo Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $41 million of increased amortization of Excess ADIT not subject to normalization requirements which impacted the ETR by (37.9)% . Amortization of Excess ADIT not subject to normalization requirements for the three months ended March 31, 2019 reflects October 2018 and March 2019 Virginia SCC Tax Reform orders as well as August 2018 and February 2019 WVPSC orders. I&M Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $13 million of increased amortization of Excess ADIT not subject to normalization requirements and an increase in favorable book/tax differences accounted for on a flow-through basis which impacted the ETR by (13.7)% and (6.1)% , respectively. Amortization of Excess ADIT not subject to normalization requirements for the three months ended March 31, 2019 reflects the Tax Reform elements of the 2017 Indiana Base Rate Case approved by the IURC in May 2018. OPCo Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $9 million of increased amortization of Excess ADIT not subject to normalization requirements which impacted the ETR by (6)% . Amortization of Excess ADIT not subject to normalization requirements for the three months ended March 31, 2019 reflects the October 2018 PUCO Tax Reform order. PSO Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $1 million of increased amortization of Excess ADIT not subject to normalization requirements which impacted the ETR by (16.9)% . Amortization of Excess ADIT not subject to normalization requirements for the three months ended March 31, 2019 reflects the August 2018 OCC Tax Reform order as well as Tax Reform elements of the 2018 Oklahoma Base Rate Case approved by the OCC in March 2019. SWEPCo Three Months Ended March 31, 2019 Compared to Three Months Ended March 31, 2018 The decrease in the ETR is primarily due to $3 million of increased amortization of Excess ADIT not subject to normalization requirements and a decrease in state tax expense which impacted the ETR by (11.3)% and (1.3)% , respectively. Amortization of Excess ADIT not subject to normalization requirements for the three months ended March 31, 2019 reflects Tax Reform elements incorporated into Louisiana’s 2018 Formula Rate Filing as well as an Arkansas Tax Reform order issued by the APSC in September 2018. Federal and State Income Tax Audit Status The IRS has completed its examination of AEP and subsidiaries for all years through 2016.

Leases

Leases	3 Months Ended
	Mar. 31, 2019
Leases	LEASES The disclosures in this note apply to all Registrants unless indicated otherwise. The Registrants lease property, plant and equipment including, but not limited to, fleet, information technology and real estate leases. These leases require payments of non-lease components, including related property taxes, operating and maintenance costs. As of the adoption date of ASU 2016-02, management elected not to separate non-lease components from associated lease components in accordance with the accounting guidance for “Leases.” Many of these leases have purchase or renewal options. Leases not renewed are often replaced by other leases. Options to renew or purchase a lease are included in the measurement of lease assets and liabilities if it is reasonably certain the Registrant will exercise the option. Lease obligations are measured using the rate implicit in the lease when that rate is readily determinable. When the implicit rate is not readily determinable, the Registrants calculate their lease obligation using their incremental borrowing rate. Spreads to estimate the discount associated with borrowing on a secured basis are incorporated into the calculation. Lease rentals for both operating and finance leases are generally charged to Other Operation and Maintenance expense in accordance with rate-making treatment for regulated operations. Additionally, for regulated operations with finance leases, a finance lease asset and offsetting liability are recorded at the present value of the remaining lease payments for each reporting period. Finance leases for nonregulated property are accounted for as if the assets were owned and financed. The components of rental costs were as follows: Three Months Ended March 31, 2019 AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Operating Lease Cost $ 64.6 $ 3.8 $ 0.6 $ 4.6 $ 23.0 $ 3.6 $ 1.5 $ 1.8 Finance Lease Cost: Amortization of Right-of-Use Assets 14.2 1.1 — 1.5 1.3 0.7 0.7 2.7 Interest on Lease Liabilities 4.1 0.3 — 0.7 0.8 0.2 0.1 0.8 Total Lease Rental Costs (a) $ 82.9 $ 5.2 $ 0.6 $ 6.8 $ 25.1 $ 4.5 $ 2.3 $ 5.3 (a) Excludes variable and short-term lease costs, which were immaterial for the three months ended March 31, 2019. Supplemental information related to leases as of and for the three months ended March 31, 2019 are shown in the tables below. Lease Term and Discount Rate AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo Weighted-Average Remaining Lease Term (years): Operating Leases 5.43 7.30 2.71 6.34 4.32 8.21 7.11 6.67 Finance Leases 5.94 7.07 1.08 6.44 6.91 6.16 6.06 5.60 Weighted-Average Discount Rate: Operating Leases 3.61 % 3.82 % 3.14 % 3.66 % 3.45 % 3.86 % 3.67 % 3.89 % Finance Leases 6.19 % 4.79 % 9.33 % 8.61 % 9.03 % 4.81 % 4.78 % 5.04 % AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Cash paid for amounts included in the measurement of lease liabilities: Operating Cash Flows from Operating Leases $ 28.9 $ 3.8 $ 0.7 $ 4.2 $ 5.0 $ 3.6 $ 1.5 $ 1.4 Operating Cash Flows from Finance Leases 3.8 0.3 — 0.7 0.7 0.2 0.1 0.7 Financing Cash Flows from Finance Leases 14.3 1.2 — 1.6 1.2 0.7 0.7 2.7 Non-cash Acquisitions Under Operating Leases $ 38.5 $ 4.6 $ — $ 3.5 $ 2.6 $ 15.8 $ 2.3 $ 2.6 The following tables show the property, plant and equipment under finance leases and noncurrent assets under operating leases and related obligations recorded on the Registrants’ balance sheets. Unless shown as a separate line on the balance sheets due to materiality, net operating lease assets are included in Deferred Charges and Other Noncurrent Assets, current finance lease obligations are included in Other Current Liabilities and long-term finance lease obligations are included in Deferred Credits and Other Noncurrent Liabilities on the Registrants’ balance sheets. Lease obligations are not recognized on the balance sheets for lease agreements with a lease term of less than twelve months. March 31, 2019 AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Property, Plant and Equipment Under Finance Leases: Generation $ 166.3 $ — $ — $ 38.6 $ 27.0 $ — $ 2.6 $ 69.4 Other Property, Plant and Equipment 277.3 39.9 0.2 17.4 33.4 21.3 18.3 11.7 Total Property, Plant and Equipment 443.6 39.9 0.2 56.0 60.4 21.3 20.9 81.1 Accumulated Amortization 149.4 10.1 0.1 15.7 21.2 6.7 8.1 22.1 Net Property, Plant and Equipment Under Finance Leases $ 294.2 $ 29.8 $ 0.1 $ 40.3 $ 39.2 $ 14.6 $ 12.8 $ 59.0 Obligations Under Finance Leases: Noncurrent Liability $ 237.4 $ 24.9 $ — $ 34.0 $ 33.7 $ 11.4 $ 9.8 $ 49.3 Liability Due Within One Year 61.5 4.9 0.1 6.3 5.5 3.2 3.0 10.6 Total Obligations Under Finance Leases $ 298.9 $ 29.8 $ 0.1 $ 40.3 $ 39.2 $ 14.6 $ 12.8 $ 59.9 March 31, 2019 AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Operating Lease Assets $ 1,045.4 $ 82.4 $ 5.8 $ 79.1 $ 326.3 $ 86.6 $ 34.8 $ 38.0 Obligations Under Operating Leases: Noncurrent Liability $ 860.2 $ 70.2 $ 3.2 $ 64.8 $ 266.0 $ 74.0 $ 29.1 $ 32.3 Liability Due Within One Year 228.2 12.2 2.6 15.0 81.8 13.0 5.7 6.1 Total Obligations Under Operating Leases $ 1,088.4 $ 82.4 $ 5.8 $ 79.8 $ 347.8 $ 87.0 $ 34.8 $ 38.4 Future minimum lease payments as of March 31, 2019 are presented on a rolling 12-month basis as shown in the tables below: Finance Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Year 1 $ 74.1 $ 6.2 $ 0.1 $ 9.2 $ 8.4 $ 3.8 $ 3.6 $ 13.2 Year 2 63.6 5.8 — 8.4 7.5 3.3 2.9 11.3 Year 3 54.9 5.1 — 7.6 6.9 2.7 2.1 10.5 Year 4 46.2 4.5 — 7.1 6.3 2.0 1.7 9.3 Year 5 38.8 3.9 — 6.6 5.9 1.5 1.4 9.3 Later Years 87.4 10.2 — 12.3 20.9 4.0 3.3 15.7 Total Future Minimum Lease Payments 365.0 35.7 0.1 51.2 55.9 17.3 15.0 69.3 Less Imputed Interest 66.1 5.9 — 10.9 16.7 2.7 2.2 9.4 Estimated Present Value of Future Minimum Lease Payments $ 298.9 $ 29.8 $ 0.1 $ 40.3 $ 39.2 $ 14.6 $ 12.8 $ 59.9 Noncancelable Operating Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Year 1 $ 263.3 $ 15.2 $ 2.7 $ 18.0 $ 92.5 $ 16.0 $ 6.8 $ 7.6 Year 2 253.3 14.4 2.0 16.5 89.5 14.4 6.4 7.4 Year 3 235.9 13.5 0.9 14.0 84.9 12.4 5.4 6.9 Year 4 226.8 12.5 0.6 12.8 85.2 11.6 5.1 6.4 Year 5 61.5 11.1 — 9.7 7.0 10.2 4.6 5.2 Later Years 180.7 29.4 — 20.5 20.4 38.6 12.1 11.1 Total Future Minimum Lease Payments 1,221.5 96.1 6.2 91.5 379.5 103.2 40.4 44.6 Less Imputed Interest 133.1 13.7 0.4 11.7 31.7 16.2 5.6 6.2 Estimated Present Value of Future Minimum Lease Payments $ 1,088.4 $ 82.4 $ 5.8 $ 79.8 $ 347.8 $ 87.0 $ 34.8 $ 38.4 Future minimum lease payments consisted of the following as of December 31, 2018 : Finance Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) 2019 $ 70.8 $ 5.8 $ 0.1 $ 9.0 $ 8.2 $ 3.3 $ 3.4 $ 13.1 2020 60.2 5.3 — 8.0 7.2 2.7 2.6 11.5 2021 51.7 4.7 — 7.3 6.6 2.3 2.0 10.5 2022 43.8 4.2 — 6.8 6.1 1.7 1.6 9.4 2023 35.5 3.7 — 6.3 5.7 1.2 1.4 8.6 Later Years 90.2 10.1 — 13.3 21.7 2.8 3.3 18.7 Total Future Minimum Lease Payments 352.2 33.8 0.1 50.7 55.5 14.0 14.3 71.8 Less Imputed Interest 63.2 5.3 — 10.9 16.8 1.9 2.0 11.0 Estimated Present Value of Future Minimum Lease Payments $ 289.0 $ 28.5 $ 0.1 $ 39.8 $ 38.7 $ 12.1 $ 12.3 $ 60.8 Noncancelable Operating Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) 2019 $ 259.6 $ 15.1 $ 2.3 $ 17.6 $ 92.6 $ 14.5 $ 6.5 $ 7.4 2020 250.1 14.1 1.8 16.5 89.3 13.2 6.0 7.2 2021 232.7 13.2 1.0 13.9 84.8 10.9 5.0 6.7 2022 222.5 12.2 0.5 12.8 83.8 10.0 4.6 6.1 2023 58.3 10.8 0.1 9.9 6.5 8.8 4.1 5.0 Later Years 165.2 28.4 — 20.5 19.5 31.7 10.7 11.7 Total Future Minimum Lease Payments $ 1,188.4 $ 93.8 $ 5.7 $ 91.2 $ 376.5 $ 89.1 $ 36.9 $ 44.1 Master Lease Agreements (Applies to all Registrants except AEPTCo) The Registrants lease certain equipment under master lease agreements. Under the lease agreements, the lessor is guaranteed a residual value up to a stated percentage of the equipment cost at the end of the lease term. If the actual fair value of the leased equipment is below the guaranteed residual value at the end of the lease term, the Registrants are committed to pay the difference between the actual fair value and the residual value guarantee. Historically, at the end of the lease term the fair value has been in excess of the amount guaranteed. As of March 31, 2019 , the maximum potential loss by the Registrants for these lease agreements assuming the fair value of the equipment is zero at the end of the lease term was as follows: Company Maximum Potential Loss (in millions) AEP $ 48.8 AEP Texas 10.9 APCo 8.9 I&M 3.9 OPCo 8.4 PSO 4.0 SWEPCo 4.4 Rockport Lease (Applies to AEP and I&M) AEGCo and I&M entered into a sale-and-leaseback transaction in 1989 with Wilmington Trust Company (Owner Trustee), an unrelated, unconsolidated trustee for Rockport Plant, Unit 2 (the Plant). The Owner Trustee was capitalized with equity from six owner participants with no relationship to AEP or any of its subsidiaries and debt from a syndicate of banks and securities in a private placement to certain institutional investors. In the first quarter of 2019, in accordance with ASU 2016-02, the $37 million unamortized gain ( $15 million related to I&M) associated with the sale-and-leaseback of the Plant was recognized as an adjustment to equity. The adjustment to equity was then reclassified to regulatory liabilities in accordance with accounting guidance for “Regulated Operations” as AEGCo and I&M will continue to provide the benefit of the unamortized gain to customers in future periods. The Owner Trustee owns the Plant and leases it equally to AEGCo and I&M. The lease is accounted for as an operating lease with the payment obligations included in the future minimum lease payments schedule earlier in this note. The lease term is for 33 years with potential renewal options. At the end of the lease term, AEGCo and I&M have the option to renew the lease at a rate that approximates fair value. The option to renew was not included in the measurement of the lease obligation as of March 31, 2019 as the option to renew was not reasonably certain. AEP, AEGCo and I&M have no ownership interest in the Owner Trustee and do not guarantee its debt. The future minimum lease payments for this sale-and-leaseback transaction as of March 31, 2019 were as follows: Future Minimum Lease Payments AEP (a) I&M (in millions) 2019 $ 147.8 $ 73.9 2020 147.8 73.9 2021 147.8 73.9 2022 147.2 73.6 Total Future Minimum Lease Payments $ 590.6 $ 295.3 (a) AEP’s future minimum lease payments include equal shares from AEGCo and I&M. AEPRO Boat and Barge Leases (Applies to AEP) In 2015, AEP sold its commercial barge transportation subsidiary, AEPRO, to a nonaffiliated party. Certain boat and barge leases acquired by the nonaffiliated party are subject to an AEP guarantee in favor of the lessor, ensuring future payments under such leases with maturities up to 2027. As of March 31, 2019 , the maximum potential amount of future payments required under the guaranteed leases was $43 million . In certain instances, AEP has no recourse against the nonaffiliated party if required to pay a lessor under a guarantee, but AEP would have access to sell the leased assets in order to recover payments made by AEP under the guarantee. As of March 31, 2019 , AEP’s boat and barge lease guarantee liability was $5 million , of which $1 million was recorded in Other Current Liabilities and $4 million was recorded in Deferred Credits and Other Noncurrent Liabilities on AEP’s balance sheet. In January 2018, S&P Global Inc. downgraded the ratings of the nonaffiliated party and set their outlook to negative. In April 2018, Moody’s Investors Service Inc. also downgraded their rating and set their outlook to negative. It is reasonably possible that enforcement of AEP’s liability for future payments under these leases could be exercised, which could reduce future net income and cash flows and impact financial condition. Lessor Activity

Financing Activities

Financing Activities	3 Months Ended
	Mar. 31, 2019
Financing Activities	FINANCING ACTIVITIES The disclosures in this note apply to all Registrants, unless indicated otherwise. Long-term Debt Outstanding (Applies to AEP) The following table details long-term debt outstanding, net of issuance costs and premiums or discounts: Type of Debt March 31, 2019 December 31, 2018 (in millions) Senior Unsecured Notes $ 19,411.6 $ 18,903.3 Pollution Control Bonds 1,590.0 1,643.8 Notes Payable 177.0 204.7 Securitization Bonds 973.0 1,111.4 Spent Nuclear Fuel Obligation (a) 275.3 273.6 Junior Subordinated Notes (b) 785.0 — Other Long-term Debt 1,214.8 1,209.9 Total Long-term Debt Outstanding 24,426.7 23,346.7 Long-term Debt Due Within One Year 1,528.5 1,698.5 Long-term Debt $ 22,898.2 $ 21,648.2 (a) Pursuant to the Nuclear Waste Policy Act of 1982, I&M, a nuclear licensee, has an obligation to the United States Department of Energy for SNF disposal. The obligation includes a one-time fee for nuclear fuel consumed prior to April 7, 1983. Trust fund assets related to this obligation were $318 million and $317 million as of March 31, 2019 and December 31, 2018 , respectively, and are included in Spent Nuclear Fuel and Decommissioning Trusts on the balance sheets. (b) See “Equity Units” section below for additional information. Long-term Debt Activity Long-term debt and other securities issued, retired and principal payments made during the first three months of 2019 are shown in the following tables: Company Type of Debt Principal Amount (a) Interest Rate Due Date Issuances: (in millions) (%) AEP Junior Subordinated Notes (b) $ 805.0 3.40 2024 APCo Senior Unsecured Notes 400.0 4.50 2049 PSO Senior Unsecured Notes 100.0 3.91 2029 Non-Registrant: Transource Energy Other Long-term Debt 6.3 Variable 2020 Total Issuances $ 1,311.3 (a) Amounts indicated on the statements of cash flows are net of issuance costs and premium or discount and will not tie to the issuance amounts. (b) See “Equity Units” section below for additional information. Company Type of Debt Principal Amount Paid Interest Rate Due Date Retirements and Principal Payments: (in millions) (%) AEP Texas Securitization Bonds $ 103.5 5.31 2020 APCo Securitization Bonds 12.0 2.01 2023 I&M Notes Payable 1.4 Variable 2019 I&M Notes Payable 1.4 Variable 2019 I&M Notes Payable 7.1 Variable 2020 I&M Notes Payable 5.9 Variable 2021 I&M Notes Payable 5.0 Variable 2022 I&M Notes Payable 5.3 Variable 2022 I&M Other Long-term Debt 0.4 6.00 2025 OPCo Securitization Bonds 23.4 2.05 2019 PSO Other Long-term Debt 0.1 3.00 2027 SWEPCo Pollution Control Bonds 53.5 1.60 2019 SWEPCo Notes Payable 1.6 4.58 2032 Total Retirements and Principal Payments $ 220.6 As of March 31, 2019 , trustees held, on behalf of AEP, $574 million of their reacquired Pollution Control Bonds. Of this total, $345 million related to OPCo. Long-term Debt Subsequent Events In April 2019, I&M retired $2 million of Notes Payable related to DCC Fuel. In April 2019, Transource Energy issued $2 million of variable rate Other Long-term Debt due in 2020 . Equity Units (Applies to AEP) In March 2019, AEP issued 16.1 million Equity Units initially in the form of corporate units, at a stated amount of $50 per unit, for a total stated amount of $805 million . Net proceeds from the issuance were approximately $785 million . The proceeds are expected to support AEP’s overall capital expenditure plans including the recent acquisition of a contracted renewable portfolio. Each corporate unit represents a 1/20 undivided beneficial ownership interest in $1,000 principal amount of AEP’s 3.40% Junior Subordinated Notes (notes) due in 2024 and a forward equity purchase contract which settles after three years in 2022. The notes are expected to be remarketed in 2022, at which time the interest rate will reset at the then current market rate. Investors may choose to remarket their notes to receive the remarketing proceeds and use those funds to settle the forward equity purchase contract, or accept the remarketed debt and use other funds for the equity purchase. If the remarketing is unsuccessful, investors have the right to put their notes to AEP at a price equal to the principal. The Equity Units carry an annual distribution rate of 6.125% , which is comprised of a quarterly coupon rate of interest of 3.40% and a quarterly forward equity purchase contract payment of 2.725% . Each forward equity purchase contract obligates the holder to purchase, and AEP to sell, for $50 a number of shares in common stock in accordance with the conversion ratios set forth below (subject to an anti-dilution adjustment): • If the AEP common stock market price is equal to or greater than $99.58 : 0.5021 shares per contract. • If the AEP common stock market price is less than $99.58 but greater than $82.98 : a number of shares per contract equal to $50 divided by the applicable market price. The holder receives a variable number of shares at $50 . • If the AEP common stock market price is less than or equal to $82.98 : 0.6026 shares per contract. A holder’s ownership interest in the notes is pledged to AEP to secure the holder’s obligation under the related forward equity purchase contract. If a holder of the forward equity purchase contract chooses at any time to no longer be a holder of the notes, such holder’s obligation under the forward equity purchase contract must be secured by a U.S. Treasury security which must be equal to the aggregate principal amount of the notes. At the time of issuance, the $805 million of notes were recorded within Long-term Debt on the balance sheets. The present value of the purchase contract payments of $62 million were recorded in Deferred Credits and Other Noncurrent Liabilities with a current portion in Other Current Liabilities at the time of issuance, representing the obligation to make forward equity contract payments, with an offsetting reduction to Paid-in Capital. The difference between the face value and present value of the purchase contract payments will be accreted to Interest Expense on the statements of income over the three year period ending in 2022. The liability recorded for the contract payments is considered non-cash and excluded from the statements of cash flows. Until settlement of the forward equity purchase contract, earnings per share dilution resulting from the equity unit issuance will be determined under the treasury stock method. The maximum amount of shares AEP will be required to issue to settle the purchase contract is 9,701,860 shares (subject to an anti-dilution adjustment). Debt Covenants (Applies to AEP and AEPTCo) Covenants in AEPTCo’s note purchase agreements and indenture limit the amount of contractually-defined priority debt (which includes a further sub-limit of $50 million of secured debt) to 10% of consolidated tangible net assets. AEPTCo’s contractually-defined priority debt was 3.0% of consolidated tangible net assets as of March 31, 2019 . The method for calculating the consolidated tangible net assets is contractually-defined in the note purchase agreements. Dividend Restrictions Utility Subsidiaries’ Restrictions Parent depends on its utility subsidiaries to pay dividends to shareholders. AEP utility subsidiaries pay dividends to Parent provided funds are legally available. Various financing arrangements and regulatory requirements may impose certain restrictions on the ability of the subsidiaries to transfer funds to Parent in the form of dividends. All of the dividends declared by AEP’s utility subsidiaries that provide transmission or local distribution services are subject to a Federal Power Act restriction that prohibits the payment of dividends out of capital accounts without regulatory approval; payment of dividends is allowed out of retained earnings only. However, the Federal Power Act creates a reserve on earnings attributable to hydroelectric generation plants. Because of their ownership of such plants, this reserve applies to AGR, APCo and I&M. Certain AEP subsidiaries have credit agreements that contain covenants that limit their debt to capitalization ratio to 67.5% . The method for calculating outstanding debt and capitalization is contractually-defined in the credit agreements. The Federal Power Act restriction does not limit the ability of the AEP subsidiaries to pay dividends out of retained earnings. Parent Restrictions (Applies to AEP) The holders of AEP’s common stock are entitled to receive the dividends declared by the Board of Directors provided funds are legally available for such dividends. Parent’s income primarily derives from common stock equity in the earnings of its utility subsidiaries. Pursuant to the leverage restrictions in credit agreements, AEP must maintain a percentage of debt to total capitalization at a level that does not exceed 67.5%. The method for calculating outstanding debt and capitalization is contractually-defined in the credit agreements. Corporate Borrowing Program - AEP System (Applies to Registrant Subsidiaries) The AEP System uses a corporate borrowing program to meet the short-term borrowing needs of AEP’s subsidiaries. The corporate borrowing program includes a Utility Money Pool, which funds AEP’s utility subsidiaries; a Nonutility Money Pool, which funds certain AEP nonutility subsidiaries; and direct borrowing from AEP. The AEP System Utility Money Pool operates in accordance with the terms and conditions of the AEP System Utility Money Pool agreement filed with the FERC. The amounts of outstanding loans to (borrowings from) the Utility Money Pool as of March 31, 2019 and December 31, 2018 are included in Advances to Affiliates and Advances from Affiliates, respectively, on the Registrant Subsidiaries’ balance sheets. The Utility Money Pool participants’ money pool activity and corresponding authorized borrowing limits for the three months ended March 31, 2019 are described in the following table: Company Maximum Borrowings from the Utility Money Pool Maximum Loans to the Utility Money Pool Average Borrowings from the Utility Money Pool Average Loans to the Utility Money Pool Net Loans to Authorized Short-term Borrowing Limit (in millions) AEP Texas $ 379.9 $ — $ 301.9 $ — $ (271.2 ) $ 500.0 AEPTCo 279.0 80.0 165.3 32.2 (191.1 ) 795.0 (a) APCo 225.4 232.2 189.3 75.9 216.6 600.0 I&M 46.3 66.0 19.0 23.2 (21.9 ) 500.0 OPCo 238.1 — 156.9 — (227.6 ) 500.0 PSO 140.5 — 89.1 — (55.2 ) 300.0 SWEPCo 100.6 81.4 41.9 24.0 (74.0 ) 350.0 (a) Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions. The activity in the above table does not include short-term lending activity of certain AEP nonutility subsidiaries. AEP Texas’ wholly-owned subsidiary, AEP Texas North Generation Company, LLC and SWEPCo’s wholly-owned subsidiary, Mutual Energy SWEPCo, LLC participate in the Nonutility Money Pool. The amounts of outstanding loans to the Nonutility Money Pool as of March 31, 2019 and December 31, 2018 are included in Advances to Affiliates on the subsidiaries’ balance sheets. The Nonutility Money Pool participants’ money pool activity for the three months ended March 31, 2019 is described in the following table: Maximum Loans Average Loans Loans to the Nonutility to the Nonutility to the Nonutility Money Pool as of Company Money Pool Money Pool March 31, 2019 (in millions) AEP Texas $ 8.0 $ 7.7 $ 7.7 SWEPCo 2.0 2.0 2.0 AEP has a direct financing relationship with AEPTCo to meet its short-term borrowing needs. The amounts of outstanding loans to (borrowings from) AEP as of March 31, 2019 and December 31, 2018 are included in Advances to Affiliates and Advances from Affiliates, respectively, on AEPTCo’s balance sheets. AEPTCo’s direct borrowing and lending activity with AEP for the three months ended March 31, 2019 is described in the following table: Authorized Maximum Maximum Average Average Borrowings from Loans to Short-term Borrowings Loans Borrowings Loans AEP as of AEP as of Borrowing from AEP to AEP from AEP to AEP March 31, 2019 March 31, 2019 Limit (in millions) $ 1.3 $ 117.6 $ 1.2 $ 61.8 $ 1.2 $ 42.7 $ 75.0 (a) (a) Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions. The maximum and minimum interest rates for funds either borrowed from or loaned to the Utility Money Pool are summarized in the following table: Three Months Ended March 31, 2019 2018 Maximum Interest Rate 3.02 % 2.42 % Minimum Interest Rate 2.73 % 1.83 % The average interest rates for funds borrowed from and loaned to the Utility Money Pool are summarized for the Registrant Subsidiaries in the following table: Average Interest Rate for Funds Average Interest Rate for Funds Borrowed from the Utility Money Pool Loaned to the Utility Money Pool for Three Months Ended March 31, for Three Months Ended March 31, Company 2019 2018 2019 2018 AEP Texas 2.86 % 2.07 % — % 1.90 % AEPTCo 2.83 % 2.06 % 2.90 % 1.92 % APCo 2.92 % 2.00 % 2.79 % 2.00 % I&M 2.80 % 2.02 % 2.87 % 2.00 % OPCo 2.85 % 2.00 % — % 2.40 % PSO 2.89 % 2.01 % — % — % SWEPCo 2.81 % 2.10 % 2.97 % 1.88 % Maximum, minimum and average interest rates for funds loaned to the Nonutility Money Pool are summarized in the following table: Three Months Ended March 31, 2019 Three Months Ended March 31, 2018 Maximum Minimum Average Maximum Minimum Average Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate for Funds for Funds for Funds for Funds for Funds for Funds Loaned to Loaned to Loaned to Loaned to Loaned to Loaned to the Nonutility the Nonutility the Nonutility the Nonutility the Nonutility the Nonutility Company Money Pool Money Pool Money Pool Money Pool Money Pool Money Pool AEP Texas 3.02 % 2.73 % 2.87 % 2.42 % 1.83 % 2.00 % SWEPCo 3.02 % 2.73 % 2.87 % 2.42 % 1.83 % 2.00 % AEPTCo’s maximum, minimum and average interest rates for funds either borrowed from or loaned to AEP are summarized in the following table: Maximum Minimum Maximum Minimum Average Average Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate Three Months for Funds for Funds for Funds for Funds for Funds for Funds Ended Borrowed Borrowed Loaned Loaned Borrowed Loaned March 31, from AEP from AEP to AEP to AEP from AEP to AEP 2019 3.02 % 2.73 % 3.02 % 2.73 % 2.87 % 2.86 % 2018 2.42 % 1.83 % 2.42 % 1.83 % 2.00 % 2.02 % Short-term Debt (Applies to AEP) Outstanding short-term debt was as follows: March 31, 2019 December 31, 2018 Type of Debt Outstanding Amount Interest Rate (a) Outstanding Interest (dollars in millions) Securitized Debt for Receivables (b) $ 750.0 2.71 % $ 750.0 2.16 % Commercial Paper 1,108.0 2.75 % 1,160.0 2.96 % Total Short-term Debt $ 1,858.0 $ 1,910.0 (a) Weighted-average rate. (b) Amount of securitized debt for receivables as accounted for under the “Transfers and Servicing” accounting guidance. Credit Facilities For a discussion of credit facilities, see “Letters of Credit” section of Note 5 . Securitized Accounts Receivable – AEP Credit (Applies to AEP) AEP Credit has a receivables securitization agreement that provides a commitment of $750 million from bank conduits to purchase receivables and includes a $125 million and a $625 million facility which expire in July 2020 and 2021, respectively. Under the securitization agreement, AEP Credit receives financing from the bank conduits for the interest in the receivables AEP Credit acquires from affiliated utility subsidiaries. These securitized transactions allow AEP Credit to repay its outstanding debt obligations, continue to purchase the operating companies’ receivables and accelerate AEP Credit’s cash collections. Accounts receivable information for AEP Credit was as follows: Three Months Ended March 31, 2019 2018 (dollars in millions) Effective Interest Rates on Securitization of Accounts Receivable 2.71 % 1.74 % Net Uncollectible Accounts Receivable Written-Off $ 6.4 $ 4.2 March 31, 2019 December 31, 2018 (in millions) Accounts Receivable Retained Interest and Pledged as Collateral Less Uncollectible Accounts $ 941.4 $ 972.5 Short-term – Securitized Debt of Receivables 750.0 750.0 Delinquent Securitized Accounts Receivable 52.7 50.3 Bad Debt Reserves Related to Securitization 29.1 27.5 Unbilled Receivables Related to Securitization 230.3 281.4 AEP Credit’s delinquent customer accounts receivable represent accounts greater than 30 days past due. Securitized Accounts Receivables – AEP Credit (Applies to Registrant Subsidiaries, except AEP Texas and AEPTCo) Under this sale of receivables arrangement, the Registrant Subsidiaries sell, without recourse, certain of their customer accounts receivable and accrued unbilled revenue balances to AEP Credit and are charged a fee based on AEP Credit’s financing costs, administrative costs and uncollectible accounts experience for each Registrant Subsidiary’s receivables. APCo does not have regulatory authority to sell its West Virginia accounts receivable. The costs of customer accounts receivable sold are reported in Other Operation expense on the Registrant Subsidiaries’ statements of income. The Registrant Subsidiaries manage and service their customer accounts receivable, which are sold to AEP Credit. AEP Credit securitizes the eligible receivables for the operating companies and retains the remainder. The amount of accounts receivable and accrued unbilled revenues under the sale of receivables agreements were: Company March 31, 2019 December 31, 2018 (in millions) APCo $ 132.4 $ 133.3 I&M 165.4 152.9 OPCo 383.8 395.2 PSO 103.2 109.7 SWEPCo 129.1 150.3 The fees paid to AEP Credit for customer accounts receivable sold were: Three Months Ended March 31, Company 2019 2018 (in millions) APCo $ 2.2 $ 1.7 I&M 2.8 2.1 OPCo 7.8 5.6 PSO 2.1 1.8 SWEPCo 2.6 1.9 The proceeds on the sale of receivables to AEP Credit were: Three Months Ended March 31, Company 2019 2018 (in millions) APCo $ 374.4 $ 400.2 I&M 478.6 459.1 OPCo 636.8 680.0 PSO 324.5 332.6 SWEPCo 371.9 397.6

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Mar. 31, 2019
Revenue from Contracts with Customers	REVENUE FROM CONTRACTS WITH CUSTOMERS The disclosures in this note apply to all Registrants, unless indicated otherwise. Disaggregated Revenues from Contracts with Customers The tables below represent AEP’s reportable segment revenues from contracts with customers, net of respective provisions for refund, by type of revenue: Three Months Ended March 31, 2019 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation & Marketing Corporate and Other Reconciling Adjustments AEP Consolidated (in millions) Retail Revenues: Residential Revenues $ 982.4 $ 586.1 $ — $ — $ — $ — $ 1,568.5 Commercial Revenues 511.2 310.9 — — — — 822.1 Industrial Revenues 532.1 123.9 — — — 1.8 657.8 Other Retail Revenues 43.3 11.1 — — — — 54.4 Total Retail Revenues 2,069.0 1,032.0 — — — 1.8 3,102.8 Wholesale and Competitive Retail Revenues: Generation Revenues (a) 224.7 — — 108.8 — (78.5 ) 255.0 Transmission Revenues (b) 73.5 99.6 255.1 — — (219.4 ) 208.8 Marketing, Competitive Retail and Renewable Revenues — — — 361.5 — — 361.5 Total Wholesale and Competitive Retail Revenues 298.2 99.6 255.1 470.3 — (297.9 ) 825.3 Other Revenues from Contracts with Customers (c) 39.5 46.0 3.1 2.3 23.3 (36.1 ) 78.1 Total Revenues from Contracts with Customers 2,406.7 1,177.6 258.2 472.6 23.3 (332.2 ) 4,006.2 Other Revenues: Alternative Revenues (c) (3.4 ) 5.0 (1.8 ) — — — (0.2 ) Other Revenues (c) — 39.4 — 9.2 2.2 — 50.8 Total Other Revenues (3.4 ) 44.4 (1.8 ) 9.2 2.2 — 50.6 Total Revenues $ 2,403.3 $ 1,222.0 $ 256.4 $ 481.8 $ 25.5 $ (332.2 ) $ 4,056.8 (a) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for Generation & Marketing was $37 million. The remaining affiliated amounts were immaterial. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEP Transmission Holdco was $198 million. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. Three Months Ended March 31, 2018 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation & Marketing Corporate and Other Reconciling Adjustments AEP Consolidated (in millions) Retail Revenues: Residential Revenues $ 1,001.2 $ 567.9 $ — $ — $ — $ — $ 1,569.1 Commercial Revenues 508.0 294.1 — — — — 802.1 Industrial Revenues 526.6 118.5 — — — — 645.1 Other Retail Revenues 43.9 10.4 — — — — 54.3 Total Retail Revenues (a) 2,079.7 990.9 — — — — 3,070.6 Wholesale and Competitive Retail Revenues: Generation Revenues (b) 217.0 — — 172.2 — (30.1 ) 359.1 Transmission Revenues (c) 75.0 94.1 219.5 — — (179.8 ) 208.8 Marketing, Competitive Retail and Renewable Revenues — — — 309.7 — — 309.7 Total Wholesale and Competitive Retail Revenues 292.0 94.1 219.5 481.9 — (209.9 ) 877.6 Other Revenues from Contracts with Customers (d) 39.9 49.7 2.0 2.2 22.0 (25.1 ) 90.7 Total Revenues from Contracts with Customers 2,411.6 1,134.7 221.5 484.1 22.0 (235.0 ) 4,038.9 Other Revenues: Alternative Revenues (d) (9.1 ) 6.0 (16.0 ) — — — (19.1 ) Other Revenues (d) 5.5 21.7 — 21.0 2.0 (21.7 ) 28.5 Total Other Revenues (3.6 ) 27.7 (16.0 ) 21.0 2.0 (21.7 ) 9.4 Total Revenues $ 2,408.0 $ 1,162.4 $ 205.5 $ 505.1 $ 24.0 $ (256.7 ) $ 4,048.3 (a) 2018 amounts have been revised to reflect the reclassification of certain customer accounts between Retail classes. This reclassification did not impact previously reported Total Retail Revenues. Management concluded that these prior period disclosure only errors were immaterial individually and in the aggregate. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for Generation & Marketing was $27 million. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEP Transmission Holdco was $162 million. The remaining affiliated amounts were immaterial. (d) Amounts include affiliated and nonaffiliated revenues. The tables below represent revenues from contracts with customers, net of respective provisions for refund, by type of revenue for the Registrant Subsidiaries: Three Months Ended March 31, 2019 AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Retail Revenues: Residential Revenues $ 120.9 $ — $ 372.5 $ 218.4 $ 471.6 $ 140.0 $ 140.1 Commercial Revenues 97.9 — 142.2 121.3 210.5 80.8 113.7 Industrial Revenues 33.0 — 147.5 138.4 89.7 71.0 81.2 Other Retail Revenues 7.3 — 19.6 1.8 3.4 18.0 2.2 Total Retail Revenues 259.1 — 681.8 479.9 775.2 309.8 337.2 Wholesale Revenues: Generation Revenues (a) — — 67.5 111.9 — 8.6 57.2 Transmission Revenues (b) 85.8 242.1 25.7 6.3 13.9 9.8 24.2 Total Wholesale Revenues 85.8 242.1 93.2 118.2 13.9 18.4 81.4 Other Revenues from Contracts with Customers (c) 6.9 3.1 13.4 21.0 39.0 5.8 7.8 Total Revenues from Contracts with Customers 351.8 245.2 788.4 619.1 828.1 334.0 426.4 Other Revenues: Alternative Revenues (d) (0.9 ) (1.7 ) 4.4 (4.8 ) 3.6 (1.2 ) (5.3 ) Other Revenues (d) 39.8 — — — 5.1 — — Total Other Revenues 38.9 (1.7 ) 4.4 (4.8 ) 8.7 (1.2 ) (5.3 ) Total Revenues $ 390.7 $ 243.5 $ 792.8 $ 614.3 $ 836.8 $ 332.8 $ 421.1 (a) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for APCo was $35 million primarily relating to the PPA with KGPCo. The remaining affiliated amounts were immaterial. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEPTCo was $195 million. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for I&M was $15 million primarily relating to the barging, urea transloading and other transportation services. The remaining affiliated amounts were immaterial. (d) Amounts include affiliated and nonaffiliated revenues. Three Months Ended March 31, 2018 AEP Texas AEPTCo (f) APCo I&M OPCo PSO SWEPCo (in millions) Retail Revenues: Residential Revenues $ 131.6 $ — $ 414.0 $ 189.0 $ 436.8 $ 141.1 $ 140.1 Commercial Revenues 99.4 — 146.6 109.6 194.5 84.3 108.3 Industrial Revenues 30.9 — 147.3 132.0 87.9 69.1 77.2 Other Retail Revenues 7.1 — 19.6 2.2 3.2 18.3 2.1 Total Retail Revenues (a) 269.0 — 727.5 432.8 722.4 312.8 327.7 Wholesale Revenues: Generation Revenues (b) — — 62.8 114.0 — 5.9 59.9 Transmission Revenues (c) 78.0 185.0 24.8 6.8 16.0 10.6 26.0 Total Wholesale Revenues 78.0 185.0 87.6 120.8 16.0 16.5 85.9 Other Revenues from Contracts with Customers (d) 7.1 2.0 11.2 22.7 42.3 4.2 6.1 Total Revenues from Contracts with Customers 354.1 187.0 826.3 576.3 780.7 333.5 419.7 Other Revenues: Alternative Revenues (e) (0.3 ) 4.7 (5.9 ) (5.0 ) 6.3 3.3 (0.3 ) Other Revenues (e) 17.8 — — 5.5 3.9 — — Total Other Revenues 17.5 4.7 (5.9 ) 0.5 10.2 3.3 (0.3 ) Total Revenues $ 371.6 $ 191.7 $ 820.4 $ 576.8 $ 790.9 $ 336.8 $ 419.4 (a) 2018 amounts have been revised to reflect the reclassification of certain customer accounts between Retail classes. This reclassification did not impact previously reported Total Retail Revenues. Management concluded that these prior period disclosure only errors were immaterial individually and in the aggregate. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for APCo was $40 million primarily relating to the PPA with KGPCo. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEPTCo was $160 million. The remaining affiliated amounts were immaterial. (d) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for I&M was $15 million primarily relating to the barging, urea transloading and other transportation services. The remaining affiliated amounts were immaterial. (e) Amounts include affiliated and nonaffiliated revenues. (f) The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information. Fixed Performance Obligations The following table represents the Registrants’ remaining fixed performance obligations satisfied over time as of March 31, 2019 . Fixed performance obligations primarily include wholesale transmission services, electricity sales for fixed amounts of energy and stand ready services into PJM’s RPM market. The Registrants Subsidiaries amounts shown in the table below include affiliated and nonaffiliated revenues. Company 2019 2020-2021 2022-2023 After 2023 Total (in millions) AEP $ 732.3 $ 199.1 $ 162.7 $ 285.7 $ 1,379.8 AEP Texas 278.2 — — — 278.2 AEPTCo 672.5 — — — 672.5 APCo 108.9 31.1 23.2 11.6 174.8 I&M 21.5 8.8 8.8 4.4 43.5 OPCo 47.4 — — — 47.4 PSO 13.6 — — — 13.6 SWEPCo 28.7 — — — 28.7 Contract Assets and Liabilities Contract assets are recognized when the Registrants have a right to consideration that is conditional upon the occurrence of an event other than the passage of time, such as future performance under a contract. The Registrants did not have any material contract assets as of March 31, 2019 and December 31, 2018. When the Registrants receive consideration, or such consideration is unconditionally due from a customer prior to transferring goods or services to the customer under the terms of a sales contract, they recognize a contract liability on the balance sheet in the amount of that consideration. Revenue for such consideration is subsequently recognized in the period or periods in which the remaining performance obligations in the contract are satisfied. The Registrants’ contract liabilities typically arise from services provided under joint use agreements for utility poles. The Registrants did not have any material contract liabilities as of March 31, 2019 and December 31, 2018. Accounts Receivable from Contracts with Customers Accounts receivable from contracts with customers are presented on the Registrants’ balance sheets within the Accounts Receivable - Customers line item. The Registrants’ balances for receivables from contracts that are not recognized in accordance with the accounting guidance for “Revenue from Contracts with Customers” included in Accounts Receivable - Customers were not material as of March 31, 2019 and December 31, 2018. See “Securitized Accounts Receivable - AEP Credit” section of Note 13 for additional information related to AEP Credit’s securitized accounts receivable. The following table represents the amount of affiliated accounts receivable from contracts with customers included in Accounts Receivable - Affiliated Companies on the Registrant Subsidiaries’ balance sheets: Company March 31, 2019 December 31, 2018 (in millions) AEPTCo $ 65.9 $ 58.6 APCo 46.3 52.5 I&M 24.0 35.3 OPCo 31.2 46.1 PSO 13.3 12.4 SWEPCo 10.6 16.3

Significant Accounting Matters

Significant Accounting Matters (Policies)	3 Months Ended
	Mar. 31, 2019
Basis of Accounting	General The unaudited condensed financial statements and footnotes were prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the SEC. Accordingly, they do not include all of the information and footnotes required by GAAP for complete annual financial statements. In the opinion of management, the unaudited condensed interim financial statements reflect all normal and recurring accruals and adjustments necessary for a fair presentation of the net income, financial position and cash flows for the interim periods for each Registrant. Net income for the three months ended March 31, 2019 is not necessarily indicative of results that may be expected for the year ending December 31, 2019 . The condensed financial statements are unaudited and should be read in conjunction with the audited 2018 financial statements and notes thereto, which are included in the Registrants’ Annual Reports on Form 10-K as filed with the SEC on February 21, 2019
Earnings Per Share	Earnings Per Share (EPS) (Applies to AEP)

Derivatives and Hedging (Polici

Derivatives and Hedging (Policies)	3 Months Ended
	Mar. 31, 2019
Derivatives and Hedging	Accounting for Cash Flow Hedging Strategies For cash flow hedges (i.e. hedging the exposure to variability in expected future cash flows that is attributable to a particular risk), the Registrants initially report the gain or loss on the derivative instrument as a component of Accumulated Other Comprehensive Income (Loss) on the balance sheets until the period the hedged item affects net income. Management mitigates credit risk in wholesale marketing and trading activities by assessing the creditworthiness of potential counterparties before entering into transactions with them and continuing to evaluate their creditworthiness on an ongoing basis. Management uses credit agency ratings and current market-based qualitative and quantitative data as well as financial statements to assess the financial health of counterparties on an ongoing basis. Master agreements are typically used to facilitate the netting of cash flows associated with a single counterparty and may include collateral requirements. Collateral requirements in the form of cash, letters of credit and parental/affiliate guarantees may be obtained as security from counterparties in order to mitigate credit risk. Some master agreements include margining, which requires a counterparty to post cash or letters of credit in the event exposure exceeds the established threshold. The threshold represents an unsecured credit limit which may be supported by a parental/affiliate guaranty, as determined in accordance with AEP’s credit policy. In addition, master agreements allow for termination and liquidation of all positions in the event of a default including a failure or inability to post collateral when required. Collateral Triggering Events Credit Downgrade Triggers (Applies to AEP, APCo, I&M, PSO and SWEPCo) Parent enters into interest rate derivative transactions as part of an overall strategy to manage the mix of fixed-rate and floating-rate debt. Certain interest rate derivative transactions effectively modify exposure to interest rate risk by converting a portion of fixed-rate debt to a floating-rate. Provided specific criteria are met, these interest rate derivatives may be designated as fair value hedges. Cash Flow Hedging Strategies The Registrants utilize cash flow hedges on certain derivative transactions for the purchase and sale of power (“Commodity”) in order to manage the variable price risk related to forecasted purchases and sales. Management monitors the potential impacts of commodity price changes and, where appropriate, enters into derivative transactions to protect profit margins for a portion of future electricity sales and purchases. The Registrants do not hedge all commodity price risk. The Registrants utilize a variety of interest rate derivative transactions in order to manage interest rate risk exposure. The Registrants also utilize interest rate derivative contracts to manage interest rate exposure related to future borrowings of fixed-rate debt. The Registrants do not hedge all interest rate exposure. At times, the Registrants are exposed to foreign currency exchange rate risks primarily when some fixed assets are purchased from foreign suppliers. In accordance with AEP’s risk management policy, the Registrants may utilize foreign currency derivative transactions to protect against the risk of increased cash outflows resulting from a foreign currency’s appreciation against the dollar. The Registrants do not hedge all foreign currency exposure. ACCOUNTING FOR DERIVATIVE INSTRUMENTS AND THE IMPACT ON THE FINANCIAL STATEMENTS The accounting guidance for “Derivatives and Hedging” requires recognition of all qualifying derivative instruments as either assets or liabilities on the balance sheets at fair value. The fair values of derivative instruments accounted for using MTM accounting or hedge accounting are based on exchange prices and broker quotes. If a quoted market price is not available, the estimate of fair value is based on the best information available including valuation models that estimate future energy prices based on existing market and broker quotes, supply and demand market data and assumptions. In order to determine the relevant fair values of the derivative instruments, the Registrants apply valuation adjustments for discounting, liquidity and credit quality. Credit risk is the risk that a counterparty will fail to perform on the contract or fail to pay amounts due. Liquidity risk represents the risk that imperfections in the market will cause the price to vary from estimated fair value based upon prevailing market supply and demand conditions. Since energy markets are imperfect and volatile, there are inherent risks related to the underlying assumptions in models used to fair value risk management contracts. Unforeseen events may cause reasonable price curves to differ from actual price curves throughout a contract’s term and at the time a contract settles. Consequently, there could be significant adverse or favorable effects on future net income and cash flows if market prices are not consistent with management’s estimates of current market consensus for forward prices in the current period. This is particularly true for longer term contracts. Cash flows may vary based on market conditions, margin requirements and the timing of settlement of risk management contracts. The accounting for the changes in the fair value of a derivative instrument depends on whether it qualifies for and has been designated as part of a hedging relationship and further, on the type of hedging relationship. Depending on the exposure, management designates a hedging instrument as a fair value hedge or a cash flow hedge. For contracts that have not been designated as part of a hedging relationship, the accounting for changes in fair value depends on whether the derivative instrument is held for trading purposes. Unrealized and realized gains and losses on derivative instruments held for trading purposes are included in revenues on a net basis on the statements of income. Unrealized and realized gains and losses on derivative instruments not held for trading purposes are included in revenues or expenses on the statements of income depending on the relevant facts and circumstances. Certain derivatives that economically hedge future commodity risk are recorded in the same expense line item on the statements of income as that of the associated risk. However, unrealized and some realized gains and losses in regulated jurisdictions for both trading and non-trading derivative instruments are recorded as regulatory assets (for losses) or regulatory liabilities (for gains) in accordance with the accounting guidance for “Regulated Operations.” Accounting for Fair Value Hedging Strategies (Applies to AEP) For fair value hedges (i.e. hedging the exposure to changes in the fair value of an asset, liability or an identified portion thereof attributable to a particular risk), the gain or loss on the derivative instrument as well as the offsetting gain or loss on the hedged item associated with the hedged risk impacts net income during the period of change. AEPSC is agent for and transacts on behalf of AEP subsidiaries, including the Registrant Subsidiaries. AEPEP is agent for and transacts on behalf of other AEP subsidiaries. The Registrants are exposed to certain market risks as major power producers and participants in the electricity, capacity, natural gas, coal and emission allowance markets. These risks include commodity price risks which may be subject to capacity risk, interest rate risk, credit risk and foreign currency exchange risk. These risks represent the risk of loss that may impact the Registrants due to changes in the underlying market prices or rates. Management utilizes derivative instruments to manage these risks. STRATEGIES FOR UTILIZATION OF DERIVATIVE INSTRUMENTS TO ACHIEVE OBJECTIVES Risk Management Strategies The strategy surrounding the use of derivative instruments primarily focuses on managing risk exposures, future cash flows and creating value utilizing both economic and formal hedging strategies. The risk management strategies also include the use of derivative instruments for trading purposes which focus on seizing market opportunities to create value driven by expected changes in the market prices of the commodities. To accomplish these objectives, the Registrants primarily employ risk management contracts including physical and financial forward purchase-and-sale contracts and, to a lesser extent, OTC swaps and options. Not all risk management contracts meet the definition of a derivative under the accounting guidance for “Derivatives and Hedging.” Derivative risk management contracts elected normal under the normal purchases and normal sales scope exception are not subject to the requirements of this accounting guidance. In addition, a majority of non-exchange-traded commodity contracts contain cross-default provisions that, if triggered, would permit the counterparty to declare a default and require settlement of the outstanding payable. These cross-default provisions could be triggered if there was a non-performance event by Parent or the obligor under outstanding debt or a third-party obligation that is $50 million

Fair Value Measurements (Polici

Fair Value Measurements (Policies)	3 Months Ended
	Mar. 31, 2019
Valuation Techniques	Fair Value Hierarchy and Valuation Techniques The accounting guidance for “Fair Value Measurements and Disclosures” establishes a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). Where observable inputs are available for substantially the full term of the asset or liability, the instrument is categorized in Level 2. When quoted market prices are not available, pricing may be completed using comparable securities, dealer values, operating data and general market conditions to determine fair value. Valuation models utilize various inputs such as commodity, interest rate and, to a lesser degree, volatility and credit that include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in inactive markets, market corroborated inputs (i.e. inputs derived principally from, or correlated to, observable market data) and other observable inputs for the asset or liability. For commercial activities, exchange-traded derivatives, namely futures contracts, are generally fair valued based on unadjusted quoted prices in active markets and are classified as Level 1. Level 2 inputs primarily consist of OTC broker quotes in moderately active or less active markets, as well as exchange-traded derivatives where there is insufficient market liquidity to warrant inclusion in Level 1. Management verifies price curves using these broker quotes and classifies these fair values within Level 2 when substantially all of the fair value can be corroborated. Management typically obtains multiple broker quotes, which are nonbinding in nature but are based on recent trades in the marketplace. When multiple broker quotes are obtained, the quoted bid and ask prices are averaged. In certain circumstances, a broker quote may be discarded if it is a clear outlier. Management uses a historical correlation analysis between the broker quoted location and the illiquid locations. If the points are highly correlated, these locations are included within Level 2 as well. Certain OTC and bilaterally executed derivative instruments are executed in less active markets with a lower availability of pricing information. Illiquid transactions, complex structured transactions, FTRs and counterparty credit risk may require nonmarket-based inputs. Some of these inputs may be internally developed or extrapolated and utilized to estimate fair value. When such inputs have a significant impact on the measurement of fair value, the instrument is categorized as Level 3. The main driver of contracts being classified as Level 3 is the inability to substantiate energy price curves in the market. A portion of the Level 3 instruments have been economically hedged which limits potential earnings volatility. AEP utilizes its trustee’s external pricing service to estimate the fair value of the underlying investments held in the nuclear trusts. AEP’s investment managers review and validate the prices utilized by the trustee to determine fair value. AEP’s management performs its own valuation testing to verify the fair values of the securities. AEP receives audit reports of the trustee’s operating controls and valuation processes. The trustee uses multiple pricing vendors for the assets held in the trusts.
Fair Values of Long-term Debt	Fair Value Measurements of Long-term Debt (Applies to all Registrants)
Trust Assets for Decommissioning and Spent Nuclear Fuel Disposal	Fair Value Measurements of Trust Assets for Decommissioning and SNF Disposal (Applies to AEP and I&M) Nuclear decommissioning and SNF trust funds represent funds that regulatory commissions allow I&M to collect through rates to fund future decommissioning and SNF disposal liabilities. By rules or orders, the IURC, the MPSC and the FERC established investment limitations and general risk management guidelines. In general, limitations include: • Acceptable investments (rated investment grade or above when purchased). • Maximum percentage invested in a specific type of investment. • Prohibition of investment in obligations of AEP, I&M or their affiliates. • Withdrawals permitted only for payment of decommissioning costs and trust expenses. I&M maintains trust funds for each regulatory jurisdiction. Regulatory approval is required to withdraw decommissioning funds. These funds are managed by external investment managers who must comply with the guidelines and rules of the applicable regulatory authorities. The trust assets are invested to optimize the net of tax earnings of the trust giving consideration to liquidity, risk, diversification and other prudent investment objectives. I&M records securities held in these trust funds in Spent Nuclear Fuel and Decommissioning Trusts on its balance sheets. I&M records these securities at fair value. I&M classifies securities in the trust funds as available-for-sale due to their long-term purpose. With the adoption of ASU 2016-01, effective January 2018, available-for-sale classification only applies to investment in debt securities. Additionally, the adoption of ASU 2016-01 required changes in fair value of equity securities to be recognized in earnings. However, due to the regulatory treatment described below, this is not applicable for I&M’s trust fund securities.
Fair Value Assets and Liabilities Measured on Recurring Basis	Fair Value Measurements of Financial Assets and Liabilities The following tables set forth, by level within the fair value hierarchy, the Registrants’ financial assets and liabilities that were accounted for at fair value on a recurring basis. As required by the accounting guidance for “Fair Value Measurements and Disclosures,” financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Management’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels. There have not been any significant changes in management’s valuation techniques.

Leases (Policies)

Leases (Policies)	3 Months Ended
	Mar. 31, 2019
Lease Policy	Lease obligations are measured using the rate implicit in the lease when that rate is readily determinable. When the implicit rate is not readily determinable, the Registrants calculate their lease obligation using their incremental borrowing rate. Spreads to estimate the discount associated with borrowing on a secured basis are incorporated into the calculation.

Significant Accounting Matter_2

Significant Accounting Matters (Tables)	3 Months Ended
	Mar. 31, 2019
Basic and Diluted EPS Calculations	Three Months Ended March 31, 2019 2018 (in millions, except per share data) $/share $/share Earnings Attributable to AEP Common Shareholders $ 572.8 $ 454.4 Weighted Average Number of Basic Shares Outstanding 493.3 $ 1.16 492.3 $ 0.92 Weighted Average Dilutive Effect of Stock-Based Awards 1.2 — 0.8 — Weighted Average Number of Diluted Shares Outstanding 494.5 $ 1.16 493.1 $ 0.92
Reconciliation of Cash, Cash Equivalents and Restricted Cash	March 31, 2019 AEP AEP Texas APCo OPCo (in millions) Cash and Cash Equivalents $ 227.7 $ 0.1 $ 2.9 $ 3.3 Restricted Cash 135.4 100.6 18.3 16.5 Total Cash, Cash Equivalents and Restricted Cash $ 363.1 $ 100.7 $ 21.2 $ 19.8 December 31, 2018 AEP AEP Texas APCo OPCo (in millions) Cash and Cash Equivalents $ 234.1 $ 3.1 $ 4.2 $ 4.9 Restricted Cash 210.0 156.7 25.6 27.6 Total Cash, Cash Equivalents and Restricted Cash $ 444.1 $ 159.8 $ 29.8 $ 32.5
Revision to Prior Year Income	Three Months Ended March 31, 2018 As Reported Adjustments As Adjusted (in millions) TOTAL REVENUES $ 193.5 $ (1.8 ) $ 191.7 EXPENSES Depreciation and Amortization 30.6 (0.3 ) 30.3 TOTAL EXPENSES 80.9 (0.3 ) 80.6 OPERATING INCOME 112.6 (1.5 ) 111.1 Other Income (Expense): Allowance for Equity Funds Used During Construction 15.3 (0.4 ) 14.9 Interest Expense (19.9 ) (0.4 ) (20.3 ) INCOME BEFORE INCOME TAX EXPENSE 108.4 (2.3 ) 106.1 Income Tax Expense 22.5 (0.5 ) 22.0 NET INCOME $ 85.9 $ (1.8 ) $ 84.1
Schedule of Error Corrections and Prior Period Adjustments	Three Months Ended March 31, 2018 As Reported Adjustments As Adjusted (in millions) OPERATING ACTIVITIES Net Income $ 85.9 $ (1.8 ) $ 84.1 Adjustments to Reconcile Net Income to Net Cash Flows from Operating Activities: Depreciation and Amortization 30.6 (0.3 ) 30.3 Deferred Income Taxes 15.7 (0.2 ) 15.5 Allowance for Equity Funds Used During Construction (15.3 ) 0.4 (14.9 ) Change in Other Noncurrent Assets 2.7 0.2 2.9 Changes in Certain Components of Working Capital: Accounts Receivable, Net (10.1 ) 0.5 (9.6 ) Accounts Payable (12.3 ) 1.6 (10.7 ) Accrued Taxes, Net (33.6 ) (0.4 ) (34.0 ) Net Cash Flows from Operating Activities 127.1 — 127.1 INVESTING ACTIVITIES Net Cash Flows Used for Investing Activities (458.4 ) — (458.4 ) FINANCING ACTIVITIES Net Cash Flows from Financing Activities 331.3 — 331.3 Net Change in Cash and Cash Equivalents — — — Cash and Cash Equivalents at Beginning of Period — — — Cash and Cash Equivalents at End of Period $ — $ — $ — SUPPLEMENTARY INFORMATION Construction Expenditures Included in Current Liabilities as of March 31, $ 210.6 $ 3.2 $ 213.8

Comprehensive Income (Tables)

Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2019
Changes in Accumulated Other Comprehensive Income (Loss) by Component	AEP Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedges Commodity Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (23.0 ) $ (12.6 ) $ (84.8 ) $ (120.4 ) Change in Fair Value Recognized in AOCI (38.8 ) — — (38.8 ) Amount of (Gain) Loss Reclassified from AOCI Purchased Electricity for Resale (a) 12.3 — — 12.3 Interest Expense (a) — 0.2 — 0.2 Amortization of Prior Service Cost (Credit) — — (4.8 ) (4.8 ) Amortization of Actuarial (Gains) Losses — — 3.0 3.0 Reclassifications from AOCI, before Income Tax (Expense) Benefit 12.3 0.2 (1.8 ) 10.7 Income Tax (Expense) Benefit 2.6 — (0.4 ) 2.2 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 9.7 0.2 (1.4 ) 8.5 Net Current Period Other Comprehensive Income (Loss) (29.1 ) 0.2 (1.4 ) (30.3 ) Balance in AOCI as of March 31, 2019 $ (52.1 ) $ (12.4 ) $ (86.2 ) $ (150.7 ) AEP Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedges Commodity Interest Rate Securities Available for Sale Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (28.4 ) $ (13.0 ) $ 11.9 $ (38.3 ) $ (67.8 ) Change in Fair Value Recognized in AOCI 12.8 — — — 12.8 Amount of (Gain) Loss Reclassified from AOCI Purchased Electricity for Resale (a) (13.1 ) — — — (13.1 ) Interest Expense (a) — 0.3 — — 0.3 Amortization of Prior Service Cost (Credit) — — — (5.0 ) (5.0 ) Amortization of Actuarial (Gains) Losses — — — 3.2 3.2 Reclassifications from AOCI, before Income Tax (Expense) Benefit (13.1 ) 0.3 — (1.8 ) (14.6 ) Income Tax (Expense) Benefit (2.8 ) 0.1 — (0.4 ) (3.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (10.3 ) 0.2 — (1.4 ) (11.5 ) Net Current Period Other Comprehensive Income (Loss) 2.5 0.2 — (1.4 ) 1.3 ASU 2018-02 Adoption (6.1 ) (2.7 ) — (8.2 ) (17.0 ) ASU 2016-01 Adoption — — (11.9 ) — (11.9 ) Balance in AOCI as of March 31, 2018 $ (32.0 ) $ (15.5 ) $ — $ (47.9 ) $ (95.4 ) AEP Texas Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (4.4 ) $ (10.7 ) $ (15.1 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.4 — 0.4 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.4 — 0.4 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.3 — 0.3 Net Current Period Other Comprehensive Income (Loss) 0.3 — 0.3 Balance in AOCI as of March 31, 2019 $ (4.1 ) $ (10.7 ) $ (14.8 ) AEP Texas Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (4.5 ) $ (8.1 ) $ (12.6 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.3 — 0.3 Amortization of Actuarial (Gains) Losses — 0.1 0.1 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.3 0.1 0.4 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.2 0.1 0.3 Net Current Period Other Comprehensive Income (Loss) 0.2 0.1 0.3 ASU 2018-02 Adoption (0.9 ) (1.8 ) (2.7 ) Balance in AOCI as of March 31, 2018 $ (5.2 ) $ (9.8 ) $ (15.0 ) APCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ 1.8 $ (6.8 ) $ (5.0 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.3 ) — (0.3 ) Amortization of Prior Service Cost (Credit) — (1.3 ) (1.3 ) Amortization of Actuarial (Gains) Losses — 0.5 0.5 Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.3 ) (0.8 ) (1.1 ) Income Tax (Expense) Benefit (0.1 ) (0.2 ) (0.3 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.2 ) (0.6 ) (0.8 ) Net Current Period Other Comprehensive Income (Loss) (0.2 ) (0.6 ) (0.8 ) Balance in AOCI as of March 31, 2019 $ 1.6 $ (7.4 ) $ (5.8 ) APCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedges Commodity Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ — $ 2.2 $ (0.9 ) $ 1.3 Change in Fair Value Recognized in AOCI (0.7 ) — — (0.7 ) Amount of (Gain) Loss Reclassified from AOCI Purchased Electricity for Resale (a) 0.9 — — 0.9 Interest Expense (a) — (0.3 ) — (0.3 ) Amortization of Prior Service Cost (Credit) — — (1.3 ) (1.3 ) Amortization of Actuarial (Gains) Losses — — 0.3 0.3 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.9 (0.3 ) (1.0 ) (0.4 ) Income Tax (Expense) Benefit 0.2 (0.1 ) (0.2 ) (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.7 (0.2 ) (0.8 ) (0.3 ) Net Current Period Other Comprehensive Income (Loss) — (0.2 ) (0.8 ) (1.0 ) ASU 2018-02 Adoption — 0.5 (0.2 ) 0.3 Balance in AOCI as of March 31, 2018 $ — $ 2.5 $ (1.9 ) $ 0.6 I&M Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (11.5 ) $ (2.3 ) $ (13.8 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.2 ) (0.2 ) Amortization of Actuarial (Gains) Losses — 0.2 0.2 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 — 0.5 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 — 0.4 Net Current Period Other Comprehensive Income (Loss) 0.4 — 0.4 Balance in AOCI as of March 31, 2019 $ (11.1 ) $ (2.3 ) $ (13.4 ) I&M Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (10.7 ) $ (1.4 ) $ (12.1 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.2 ) (0.2 ) Amortization of Actuarial (Gains) Losses — 0.2 0.2 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 — 0.5 Income Tax (Expense) Benefit 0.1 — 0.1 Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 — 0.4 Net Current Period Other Comprehensive Income (Loss) 0.4 — 0.4 ASU 2018-02 Adoption (2.4 ) (0.3 ) (2.7 ) Balance in AOCI as of March 31, 2018 $ (12.7 ) $ (1.7 ) $ (14.4 ) OPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2018 $ 1.0 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.4 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.4 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.3 ) Net Current Period Other Comprehensive Income (Loss) (0.3 ) Balance in AOCI as of March 31, 2019 $ 0.7 OPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2017 $ 1.9 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.4 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.4 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.3 ) Net Current Period Other Comprehensive Income (Loss) (0.3 ) ASU 2018-02 Adoption 0.4 Balance in AOCI as of March 31, 2018 $ 2.0 PSO Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2018 $ 2.1 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.3 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.3 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.2 ) Net Current Period Other Comprehensive Income (Loss) (0.2 ) Balance in AOCI as of March 31, 2019 $ 1.9 PSO Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate (in millions) Balance in AOCI as of December 31, 2017 $ 2.6 Change in Fair Value Recognized in AOCI — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) (0.3 ) Reclassifications from AOCI, before Income Tax (Expense) Benefit (0.3 ) Income Tax (Expense) Benefit (0.1 ) Reclassifications from AOCI, Net of Income Tax (Expense) Benefit (0.2 ) Net Current Period Other Comprehensive Income (Loss) (0.2 ) ASU 2018-02 Adoption 0.5 Balance in AOCI as of March 31, 2018 $ 2.9 SWEPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2019 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2018 $ (3.3 ) $ (2.1 ) $ (5.4 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.5 ) (0.5 ) Amortization of Actuarial (Gains) Losses — 0.1 0.1 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 (0.4 ) 0.1 Income Tax (Expense) Benefit 0.1 (0.1 ) — Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 (0.3 ) 0.1 Net Current Period Other Comprehensive Income (Loss) 0.4 (0.3 ) 0.1 Balance in AOCI as of March 31, 2019 $ (2.9 ) $ (2.4 ) $ (5.3 ) SWEPCo Changes in Accumulated Other Comprehensive Income (Loss) by Component For the Three Months Ended March 31, 2018 Cash Flow Hedge – Interest Rate Pension and OPEB Total (in millions) Balance in AOCI as of December 31, 2017 $ (6.0 ) $ 2.0 $ (4.0 ) Change in Fair Value Recognized in AOCI — — — Amount of (Gain) Loss Reclassified from AOCI Interest Expense (a) 0.5 — 0.5 Amortization of Prior Service Cost (Credit) — (0.5 ) (0.5 ) Amortization of Actuarial (Gains) Losses — 0.1 0.1 Reclassifications from AOCI, before Income Tax (Expense) Benefit 0.5 (0.4 ) 0.1 Income Tax (Expense) Benefit 0.1 (0.1 ) — Reclassifications from AOCI, Net of Income Tax (Expense) Benefit 0.4 (0.3 ) 0.1 Net Current Period Other Comprehensive Income (Loss) 0.4 (0.3 ) 0.1 ASU 2018-02 Adoption (1.3 ) 0.4 (0.9 ) Balance in AOCI as of March 31, 2018 $ (6.9 ) $ 2.1 $ (4.8 ) (a)

Rate Matters (Tables)

Rate Matters (Tables)	3 Months Ended
	Mar. 31, 2019
Regulated Generating Unit Expected to be Retired by 2020 [Table Text Block]	Gross Investment Accumulated Depreciation Net Investment Accelerated Depreciation Regulatory Asset (a) Materials and Supplies Cost of Removal Regulatory Liability Expected Retirement Date Remaining Recovery Period (dollars in millions) $ 106.5 $ 68.7 $ 37.8 $ 10.9 $ 3.1 $ 5.0 2020 27 years (a)
Regulatory Assets Pending Final Regulatory Approval	AEP March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Plant Retirement Costs - Unrecovered Plant $ 50.3 $ 50.3 Kentucky Deferred Purchase Power Expenses 18.4 14.5 Other Regulatory Assets Pending Final Regulatory Approval 16.4 14.8 Regulatory Assets Currently Not Earning a Return Storm Related Costs (a) 152.0 152.4 Plant Retirement Costs - Asset Retirement Obligation Costs 35.3 35.3 Other Regulatory Assets Pending Final Regulatory Approval 15.4 20.7 Total Regulatory Assets Pending Final Regulatory Approval (b) $ 287.8 $ 288.0 (a) As of March 31, 2019 , AEP Texas has deferred $137 million related to Hurricane Harvey. In March 2019, AEP Texas filed a request to securitize total estimated distribution-related system restoration costs with the PUCT. See “Texas Storm Cost Securitization” discussion below for additional information. (b) In 2015, APCo recorded a $91 million reduction to accumulated depreciation related to the remaining net book value of plants retired in 2015, primarily in its Virginia jurisdiction. These plants were normal retirements at the end of their depreciable lives under the group composite method of depreciation. APCo’s recovery of the remaining Virginia net book value for the retired plants will be considered in the Virginia SCC’s 2020 triennial review of APCo’s generation and distribution base rates. AEP Texas March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Not Earning a Return Storm-Related Costs (a) $ 152.0 $ 152.4 Rate Case Expense 0.4 0.2 Total Regulatory Assets Pending Final Regulatory Approval $ 152.4 $ 152.6 (a) As of March 31, 2019 , AEP Texas has deferred $137 million related to Hurricane Harvey. In March 2019, AEP Texas filed a request to securitize total estimated distribution-related system restoration costs with the PUCT. See “Texas Storm Cost Securitization” discussion below for additional information. APCo March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Plant Retirement Costs - Materials and Supplies $ 5.1 $ 9.0 Regulatory Assets Currently Not Earning a Return Plant Retirement Costs - Asset Retirement Obligation Costs 35.3 35.3 Other Regulatory Assets Pending Final Regulatory Approval — 0.6 Total Regulatory Assets Pending Final Regulatory Approval (a) $ 40.4 $ 44.9 (a) In 2015, APCo recorded a $91 million reduction to accumulated depreciation related to the remaining net book value of plants retired in 2015, primarily in its Virginia jurisdiction. These plants were normal retirements at the end of their depreciable lives under the group composite method of depreciation. APCo’s recovery of the remaining Virginia net book value for the retired plants will be considered in the Virginia SCC’s 2020 triennial review of APCo’s generation and distribution base rates. I&M March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Not Earning a Return Other Regulatory Assets Pending Final Regulatory Approval $ 3.4 $ 3.3 Total Regulatory Assets Pending Final Regulatory Approval $ 3.4 $ 3.3 OPCo March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Not Earning a Return Other Regulatory Assets Pending Final Regulatory Approval $ 0.1 $ 1.0 Total Regulatory Assets Pending Final Regulatory Approval $ 0.1 $ 1.0 PSO March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Oklaunion Power Station Accelerated Depreciation $ 10.9 $ 5.5 Total Regulatory Assets Pending Final Regulatory Approval $ 10.9 $ 5.5 SWEPCo March 31, December 31, 2019 2018 Noncurrent Regulatory Assets (in millions) Regulatory Assets Currently Earning a Return Plant Retirement Costs - Unrecovered Plant $ 50.3 $ 50.3 Other Regulatory Assets Pending Final Regulatory Approval 0.3 0.3 Regulatory Assets Currently Not Earning a Return Asset Retirement Obligation - Arkansas, Louisiana 5.8 5.3 Rate Case Expense - Texas 0.9 4.9 Other Regulatory Assets Pending Final Regulatory Approval 3.7 3.6 Total Regulatory Assets Pending Final Regulatory Approval $ 61.0 $ 64.4
Total Estimated Distribution-Related System Restoration Costs [Table Text Block]	Total Estimated Distribution-Related System Restoration Costs (in millions) Distribution-Related System Restoration Costs $ 264.6 Estimated Carrying Costs 26.9 Up-front Qualified Costs 4.6 Total Distribution-Related System Restoration Costs 296.1 less: Insurance Proceeds and Government Grants (3.1 ) Excess ADIT (a) (63.5 ) Total Requested Distribution-Related System Restoration Costs $ 229.5 (a)

Commitments, Guarantees and C_2

Commitments, Guarantees and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2019
Maximum Future Payments for Letters of Credit Uncommitted Facilities	Company Amount Maturity (in millions) AEP $ 105.8 June 2019 to March 2020 AEP Texas 2.2 January 2020 OPCo 1.2 September 2019 to March 2020

Benefit Plans (Tables)

Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2019
Components of Net Periodic Benefit Cost	AEP Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 23.9 $ 24.4 $ 2.4 $ 2.9 Interest Cost 51.1 46.9 12.6 11.8 Expected Return on Plan Assets (74.0 ) (72.5 ) (23.4 ) (25.5 ) Amortization of Prior Service Credit — — (17.3 ) (17.3 ) Amortization of Net Actuarial Loss 14.4 21.3 5.5 2.6 Net Periodic Benefit Cost (Credit) $ 15.4 $ 20.1 $ (20.2 ) $ (25.5 ) AEP Texas Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.1 $ 2.3 $ 0.2 $ 0.3 Interest Cost 4.4 4.0 1.0 0.9 Expected Return on Plan Assets (6.4 ) (6.4 ) (2.0 ) (2.1 ) Amortization of Prior Service Credit — — (1.5 ) (1.5 ) Amortization of Net Actuarial Loss 1.2 1.8 0.5 0.2 Net Periodic Benefit Cost (Credit) $ 1.3 $ 1.7 $ (1.8 ) $ (2.2 ) APCo Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.4 $ 2.3 $ 0.3 $ 0.3 Interest Cost 6.3 5.9 2.2 2.0 Expected Return on Plan Assets (9.4 ) (9.1 ) (3.7 ) (4.0 ) Amortization of Prior Service Credit — — (2.5 ) (2.5 ) Amortization of Net Actuarial Loss 1.8 2.6 0.9 0.5 Net Periodic Benefit Cost (Credit) $ 1.1 $ 1.7 $ (2.8 ) $ (3.7 ) I&M Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 3.4 $ 3.4 $ 0.3 $ 0.4 Interest Cost 6.0 5.5 1.5 1.4 Expected Return on Plan Assets (9.2 ) (8.9 ) (2.8 ) (3.1 ) Amortization of Prior Service Credit — — (2.4 ) (2.4 ) Amortization of Net Actuarial Loss 1.6 2.5 0.7 0.3 Net Periodic Benefit Cost (Credit) $ 1.8 $ 2.5 $ (2.7 ) $ (3.4 ) OPCo Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.0 $ 2.0 $ 0.2 $ 0.2 Interest Cost 4.7 4.4 1.4 1.3 Expected Return on Plan Assets (7.3 ) (7.2 ) (2.7 ) (3.0 ) Amortization of Prior Service Credit — — (1.7 ) (1.7 ) Amortization of Net Actuarial Loss 1.3 2.0 0.6 0.3 Net Periodic Benefit Cost (Credit) $ 0.7 $ 1.2 $ (2.2 ) $ (2.9 ) PSO Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 1.6 $ 1.8 $ 0.2 $ 0.2 Interest Cost 2.6 2.4 0.7 0.6 Expected Return on Plan Assets (4.1 ) (4.0 ) (1.3 ) (1.4 ) Amortization of Prior Service Credit — — (1.1 ) (1.0 ) Amortization of Net Actuarial Loss 0.8 1.1 0.3 0.1 Net Periodic Benefit Cost (Credit) $ 0.9 $ 1.3 $ (1.2 ) $ (1.5 ) SWEPCo Pension Plans OPEB Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 (in millions) Service Cost $ 2.1 $ 2.3 $ 0.2 $ 0.3 Interest Cost 3.1 2.9 0.8 0.7 Expected Return on Plan Assets (4.4 ) (4.4 ) (1.5 ) (1.6 ) Amortization of Prior Service Credit — — (1.3 ) (1.3 ) Amortization of Net Actuarial Loss 0.9 1.3 0.3 0.1 Net Periodic Benefit Cost (Credit) $ 1.7 $ 2.1 $ (1.5 ) $ (1.8 )

Business Segments (Tables)

Business Segments (Tables)	3 Months Ended
	Mar. 31, 2019
Reportable Segment Information	Three Months Ended March 31, 2019 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Adjustments Consolidated (in millions) Revenues from: External Customers $ 2,372.3 $ 1,179.8 $ 61.2 $ 439.7 $ 3.8 $ — $ 4,056.8 Other Operating Segments 31.0 42.2 195.2 42.1 21.7 (332.2 ) — Total Revenues $ 2,403.3 $ 1,222.0 $ 256.4 $ 481.8 $ 25.5 $ (332.2 ) $ 4,056.8 Net Income (Loss) $ 303.6 $ 156.5 $ 125.2 $ 39.2 $ (50.4 ) $ — $ 574.1 Three Months Ended March 31, 2018 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Adjustments Consolidated (in millions) Revenues from: External Customers $ 2,381.5 $ 1,141.2 $ 41.1 $ 477.5 $ 7.0 $ — $ 4,048.3 Other Operating Segments 26.5 21.2 164.4 27.6 17.0 (256.7 ) — Total Revenues $ 2,408.0 $ 1,162.4 $ 205.5 $ 505.1 $ 24.0 $ (256.7 ) $ 4,048.3 Net Income (Loss) $ 232.8 $ 125.4 $ 104.8 $ 18.1 $ (24.4 ) $ — $ 456.7 March 31, 2019 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Consolidated (in millions) Total Property, Plant and Equipment $ 45,684.3 $ 18,526.1 $ 8,973.2 $ 915.6 $ 406.4 $ (354.4 ) (b) $ 74,151.2 Accumulated Depreciation and Amortization 13,944.5 3,856.1 318.8 58.7 190.9 (186.4 ) (b) 18,182.6 Total Property Plant and Equipment - Net $ 31,739.8 $ 14,670.0 $ 8,654.4 $ 856.9 $ 215.5 $ (168.0 ) (b) $ 55,968.6 Total Assets $ 40,085.7 $ 17,419.0 $ 9,790.2 $ 1,960.1 $ 4,341.2 (c) $ (2,874.2 ) (b) (d) $ 70,722.0 Long-term Debt Due Within One Year: Nonaffiliated $ 912.1 533.3 85.0 — (1.9 ) (e) — $ 1,528.5 Long-term Debt: Affiliated 50.0 — — 32.2 — (82.2 ) — Nonaffiliated 11,999.5 4,938.6 2,895.3 (0.3 ) 3,065.1 — 22,898.2 Total Long-term Debt $ 12,961.6 $ 5,471.9 $ 2,980.3 $ 31.9 $ 3,063.2 (e) $ (82.2 ) $ 24,426.7 December 31, 2018 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation Corporate and Other (a) Reconciling Consolidated (in millions) Total Property, Plant and Equipment $ 45,365.1 $ 18,126.7 $ 8,659.5 $ 893.3 $ 395.2 $ (354.6 ) (b) $ 73,085.2 Accumulated Depreciation and Amortization 13,822.5 3,833.7 282.8 47.0 186.6 (186.5 ) (b) 17,986.1 Total Property Plant and Equipment - Net $ 31,542.6 $ 14,293.0 $ 8,376.7 $ 846.3 $ 208.6 $ (168.1 ) (b) $ 55,099.1 Total Assets $ 38,874.3 $ 17,083.4 $ 9,543.7 $ 1,979.7 $ 4,036.5 (c) $ (2,714.8 ) (b) (d) $ 68,802.8 Long-term Debt Due Within One Year: Nonaffiliated $ 1,066.3 $ 549.1 $ 85.0 $ 0.1 $ (2.0 ) (e) $ — $ 1,698.5 Long-term Debt: Affiliated 50.0 — — 32.2 — (82.2 ) — Nonaffiliated 11,442.7 5,048.8 2,888.6 (0.3 ) 2,268.4 — 21,648.2 Total Long-term Debt $ 12,559.0 $ 5,597.9 $ 2,973.6 $ 32.0 $ 2,266.4 (e) $ (82.2 ) $ 23,346.7 (a) Corporate and Other primarily includes the purchasing of receivables from certain AEP utility subsidiaries. This segment also includes 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 finance lease. (c) Includes elimination of AEP Parent’s investments in wholly-owned subsidiary companies. (d) Reconciling Adjustments for Total Assets primarily include elimination of intercompany advances to affiliates and intercompany accounts receivable. (e) Amounts reflect the impact of fair value hedge accounting. See “Accounting for Fair Value Hedging Strategies” section of Note 10 for additional information. Three Months Ended March 31, 2019 State Transcos AEPTCo Parent Reconciling Adjustments AEPTCo Consolidated (in millions) Revenues from: External Customers $ 50.3 $ — $ — $ 50.3 Sales to AEP Affiliates 193.2 — — 193.2 Total Revenues $ 243.5 $ — $ — $ 243.5 Interest Income $ 0.2 $ 28.4 $ (27.9 ) (a) $ 0.7 Interest Expense 21.7 27.9 (27.9 ) (a) 21.7 Income Tax Expense 27.6 — — 27.6 Net Income $ 104.2 $ 0.1 (b) — $ 104.3 Three Months Ended March 31, 2018 State Transcos (f) AEPTCo Parent Reconciling Adjustments AEPTCo Consolidated (f) (in millions) Revenues from: External Customers $ 30.9 $ — $ — $ 30.9 Sales to AEP Affiliates 160.7 — — 160.7 Other Revenues 0.1 — — 0.1 Total Revenues $ 191.7 $ — $ — $ 191.7 Interest Income $ 0.2 $ 25.0 $ (24.8 ) (a) $ 0.4 Interest Expense 20.3 24.8 (24.8 ) (a) 20.3 Income Tax Expense 21.7 0.3 — 22.0 Net Income $ 84.1 $ — $ — $ 84.1 March 31, 2019 State Transcos AEPTCo Parent Reconciling Adjustments AEPTCo (in millions) Total Transmission Property $ 8,567.2 $ — $ — $ 8,567.2 Accumulated Depreciation and Amortization 306.7 — — 306.7 Total Transmission Property – Net $ 8,260.5 $ — $ — $ 8,260.5 Notes Receivable – Affiliated $ — $ 2,823.4 $ (2,823.4 ) (c) $ — Total Assets $ 8,584.0 $ 2,928.1 (d) $ (2,896.0 ) (e) $ 8,616.1 Total Long-term Debt $ 2,850.0 $ 2,823.4 $ (2,850.0 ) (c) $ 2,823.4 December 31, 2018 State Transcos AEPTCo Parent Reconciling Adjustments AEPTCo (in millions) Total Transmission Property $ 8,268.1 $ — $ — $ 8,268.1 Accumulated Depreciation and Amortization 271.9 — — 271.9 Total Transmission Property – Net $ 7,996.2 $ — $ — $ 7,996.2 Notes Receivable – Affiliated $ — $ 2,823.0 $ (2,823.0 ) (c) $ — Total Assets $ 8,406.8 $ 2,857.1 (d) $ (2,869.8 ) (e) $ 8,394.1 Total Long-term Debt $ 2,850.0 $ 2,823.0 $ (2,850.0 ) (c) $ 2,823.0 (a) Elimination of intercompany interest income/interest expense on affiliated debt arrangement. (b) Includes the elimination of AEPTCo Parent’s equity earnings in the State Transcos. (c) Elimination of intercompany debt. (d) Includes the elimination of AEPTCo Parent’s investments in State Transcos. (e) Primarily relates to the elimination of Notes Receivable from the State Transcos. (f)

Derivatives and Hedging (Tables

Derivatives and Hedging (Tables)	3 Months Ended
	Mar. 31, 2019
Notional Volume of Derivative Instruments	Notional Volume of Derivative Instruments March 31, 2019 Primary Risk Exposure Unit of Measure AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Commodity: Power MWhs 310.4 — 43.9 25.9 7.6 7.8 2.0 Natural Gas MMBtus 80.6 — 4.0 2.3 — — 14.3 Heating Oil and Gasoline Gallons 5.4 1.1 1.0 0.5 1.3 0.5 0.6 Interest Rate USD $ 33.8 $ — $ — $ — $ — $ — $ — Interest Rate USD $ 500.0 $ — $ — $ — $ — $ — $ — Notional Volume of Derivative Instruments December 31, 2018 Primary Risk Exposure Unit of Measure AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Commodity: Power MWhs 371.1 — 66.4 40.9 7.8 15.2 4.5 Natural Gas MMBtus 87.9 — 4.0 2.3 — — 15.2 Heating Oil and Gasoline Gallons 7.4 1.5 1.4 0.7 1.8 0.7 0.8 Interest Rate USD $ 37.7 $ — $ — $ — $ — $ — $ — Interest Rate USD $ 500.0 $ — $ — $ — $ — $ — $ —
Fair Value of Derivative Instruments	AEP Fair Value of Derivative Instruments March 31, 2019 Risk Management Contracts Hedging Contracts Gross Amounts of Risk Management Assets/ Liabilities Recognized Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) Balance Sheet Location Commodity (a) Commodity (a) Interest Rate (a) (in millions) Current Risk Management Assets $ 228.3 $ 20.8 $ — $ 249.1 $ (155.2 ) $ 93.9 Long-term Risk Management Assets 279.0 7.4 — 286.4 (36.0 ) 250.4 Total Assets 507.3 28.2 — 535.5 (191.2 ) 344.3 Current Risk Management Liabilities 195.9 15.4 1.9 213.2 (149.8 ) 63.4 Long-term Risk Management Liabilities 236.6 68.6 4.4 309.6 (41.7 ) 267.9 Total Liabilities 432.5 84.0 6.3 522.8 (191.5 ) 331.3 Total MTM Derivative Contract Net Assets (Liabilities) $ 74.8 $ (55.8 ) $ (6.3 ) $ 12.7 $ 0.3 $ 13.0 Fair Value of Derivative Instruments December 31, 2018 Risk Management Contracts Hedging Contracts Gross Amounts of Risk Management Assets/ Liabilities Recognized Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) Balance Sheet Location Commodity (a) Commodity (a) Interest Rate (a) (in millions) Current Risk Management Assets $ 397.5 $ 28.5 $ — $ 426.0 $ (263.2 ) $ 162.8 Long-term Risk Management Assets 276.4 16.0 — 292.4 (38.4 ) 254.0 Total Assets 673.9 44.5 — 718.4 (301.6 ) 416.8 Current Risk Management Liabilities 293.8 13.2 2.0 309.0 (254.0 ) 55.0 Long-term Risk Management Liabilities 225.7 56.1 15.4 297.2 (33.8 ) 263.4 Total Liabilities 519.5 69.3 17.4 606.2 (287.8 ) 318.4 Total MTM Derivative Contract Net Assets (Liabilities) $ 154.4 $ (24.8 ) $ (17.4 ) $ 112.2 $ (13.8 ) $ 98.4 AEP Texas Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 0.2 — 0.2 Long-term Risk Management Liabilities — — — Total Liabilities 0.2 — 0.2 Total MTM Derivative Contract Net Liabilities $ (0.2 ) $ — $ (0.2 ) Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 0.7 (0.5 ) 0.2 Long-term Risk Management Liabilities — — — Total Liabilities 0.7 (0.5 ) 0.2 Total MTM Derivative Contract Net Assets (Liabilities) $ (0.7 ) $ 0.5 $ (0.2 ) APCo Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 40.5 $ (27.6 ) $ 12.9 Long-term Risk Management Assets 3.9 (3.6 ) 0.3 Total Assets 44.4 (31.2 ) 13.2 Current Risk Management Liabilities 33.5 (27.4 ) 6.1 Long-term Risk Management Liabilities 3.7 (3.5 ) 0.2 Total Liabilities 37.2 (30.9 ) 6.3 Total MTM Derivative Contract Net Assets (Liabilities) $ 7.2 $ (0.3 ) $ 6.9 Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 114.4 $ (57.2 ) $ 57.2 Long-term Risk Management Assets 3.1 (2.2 ) 0.9 Total Assets 117.5 (59.4 ) 58.1 Current Risk Management Liabilities 56.7 (56.3 ) 0.4 Long-term Risk Management Liabilities 2.4 (2.2 ) 0.2 Total Liabilities 59.1 (58.5 ) 0.6 Total MTM Derivative Contract Net Assets (Liabilities) $ 58.4 $ (0.9 ) $ 57.5 I&M Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 22.0 $ (17.6 ) $ 4.4 Long-term Risk Management Assets 2.3 (2.2 ) 0.1 Total Assets 24.3 (19.8 ) 4.5 Current Risk Management Liabilities 17.6 (17.3 ) 0.3 Long-term Risk Management Liabilities 2.2 (2.1 ) 0.1 Total Liabilities 19.8 (19.4 ) 0.4 Total MTM Derivative Contract Net Assets (Liabilities) $ 4.5 $ (0.4 ) $ 4.1 Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 50.4 $ (41.8 ) $ 8.6 Long-term Risk Management Assets 2.0 (1.4 ) 0.6 Total Assets 52.4 (43.2 ) 9.2 Current Risk Management Liabilities 41.1 (40.8 ) 0.3 Long-term Risk Management Liabilities 1.6 (1.5 ) 0.1 Total Liabilities 42.7 (42.3 ) 0.4 Total MTM Derivative Contract Net Assets (Liabilities) $ 9.7 $ (0.9 ) $ 8.8 OPCo Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 6.9 — 6.9 Long-term Risk Management Liabilities 99.4 — 99.4 Total Liabilities 106.3 — 106.3 Total MTM Derivative Contract Net Liabilities $ (106.3 ) $ — $ (106.3 ) Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ — $ — $ — Long-term Risk Management Assets — — — Total Assets — — — Current Risk Management Liabilities 6.4 (0.6 ) 5.8 Long-term Risk Management Liabilities 93.8 — 93.8 Total Liabilities 100.2 (0.6 ) 99.6 Total MTM Derivative Contract Net Assets (Liabilities) $ (100.2 ) $ 0.6 $ (99.6 ) PSO Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 5.4 $ (0.4 ) $ 5.0 Long-term Risk Management Assets — — — Total Assets 5.4 (0.4 ) 5.0 Current Risk Management Liabilities 1.1 (0.4 ) 0.7 Long-term Risk Management Liabilities — — — Total Liabilities 1.1 (0.4 ) 0.7 Total MTM Derivative Contract Net Assets $ 4.3 $ — $ 4.3 Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 10.9 $ (0.5 ) $ 10.4 Long-term Risk Management Assets — — — Total Assets 10.9 (0.5 ) 10.4 Current Risk Management Liabilities 1.7 (0.7 ) 1.0 Long-term Risk Management Liabilities — — — Total Liabilities 1.7 (0.7 ) 1.0 Total MTM Derivative Contract Net Assets $ 9.2 $ 0.2 $ 9.4 SWEPCo Fair Value of Derivative Instruments March 31, 2019 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 2.3 $ (0.3 ) $ 2.0 Long-term Risk Management Assets — — — Total Assets 2.3 (0.3 ) 2.0 Current Risk Management Liabilities 0.5 (0.3 ) 0.2 Long-term Risk Management Liabilities 1.9 — 1.9 Total Liabilities 2.4 (0.3 ) 2.1 Total MTM Derivative Contract Net Liabilities $ (0.1 ) $ — $ (0.1 ) Fair Value of Derivative Instruments December 31, 2018 Balance Sheet Location Risk Management Contracts - Commodity (a) Gross Amounts Offset in the Statement of Financial Position (b) Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position (c) (in millions) Current Risk Management Assets $ 5.6 $ (0.8 ) $ 4.8 Long-term Risk Management Assets — — — Total Assets 5.6 (0.8 ) 4.8 Current Risk Management Liabilities 1.5 (1.1 ) 0.4 Long-term Risk Management Liabilities 2.2 — 2.2 Total Liabilities 3.7 (1.1 ) 2.6 Total MTM Derivative Contract Net Assets $ 1.9 $ 0.3 $ 2.2 (a) Derivative instruments within these categories are reported gross. These instruments are subject to master netting agreements and are presented on the balance sheets on a net basis in accordance with the accounting guidance for “Derivatives and Hedging.” (b) Amounts include counterparty netting of risk management and hedging contracts and associated cash collateral in accordance with the accounting guidance for “Derivatives and Hedging.” (c)
Amount of Gain (Loss) Recognized on Risk Management Contracts	Amount of Gain (Loss) Recognized on Risk Management Contracts Three Months Ended March 31, 2019 Location of Gain (Loss) AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Vertically Integrated Utilities Revenues $ 0.3 $ — $ — $ — $ — $ — $ — Generation & Marketing Revenues 2.7 — — — — — — Electric Generation, Transmission and Distribution Revenues — — (0.1 ) 0.3 — — 0.1 Purchased Electricity for Resale 1.4 — — — — — — Other Operation (0.4 ) (0.1 ) (0.1 ) — (0.1 ) — — Maintenance (0.5 ) (0.1 ) — — (0.1 ) — (0.1 ) Regulatory Assets (a) (6.4 ) 0.6 (2.1 ) 0.3 (8.9 ) 0.5 (0.1 ) Regulatory Liabilities (a) (22.0 ) — (31.7 ) 6.6 — 6.2 4.7 Total Gain (Loss) on Risk Management Contracts $ (24.9 ) $ 0.4 $ (34.0 ) $ 7.2 $ (9.1 ) $ 6.7 $ 4.6 Amount of Gain (Loss) Recognized on Risk Management Contracts Three Months Ended March 31, 2018 Location of Gain (Loss) AEP AEP Texas APCo I&M OPCo PSO SWEPCo (in millions) Vertically Integrated Utilities Revenues $ (5.5 ) $ — $ — $ — $ — $ — $ — Generation & Marketing Revenues (15.1 ) — — — — — — Electric Generation, Transmission and Distribution Revenues — — (0.3 ) (5.1 ) — — — Purchased Electricity for Resale 4.9 — 4.6 0.2 — — — Other Operation 0.3 0.1 — — 0.1 — — Maintenance 0.4 0.1 0.1 — 0.1 — — Regulatory Assets (a) 37.3 — — 6.2 31.4 — (0.3 ) Regulatory Liabilities (a) 87.0 (0.1 ) 64.1 0.2 — 12.1 (0.8 ) Total Gain (Loss) on Risk Management Contracts $ 109.3 $ 0.1 $ 68.5 $ 1.5 $ 31.6 $ 12.1 $ (1.1 ) (a)
Impact of Fair Value Hedges on Balance Sheet [Table Text Block]	Carrying Amount of the Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) March 31, 2019 December 31, 2018 March 31, 2019 December 31, 2018 (in millions) Long-term Debt (a) $ (489.6 ) $ (478.3 ) $ 6.3 $ 17.4 (a)
Derivative Instruments, Gain (Loss)	Three Months Ended March 31, 2019 2018 (in millions) Gain (Loss) on Interest Rate Contracts: Gain (Loss) on Fair Value Hedging Instruments (a) $ 11.1 $ (14.5 ) Gain (Loss) on Fair Value Portion of Long-term Debt (a) (11.1 ) 14.5 (a)
Impact of Cash Flow Hedges on the Condensed Balance Sheet	Impact of Cash Flow Hedges on AEP’s Balance Sheets March 31, 2019 December 31, 2018 Commodity Interest Rate Commodity Interest Rate (in millions) AOCI Gain (Loss) Net of Tax (52.1 ) (12.4 ) (23.0 ) (12.6 ) Portion Expected to be Reclassed to Net Income During the Next Twelve Months 1.6 (1.5 ) 10.4 (1.1 ) March 31, 2019 December 31, 2018 Interest Rate Company AOCI Gain (Loss) Net of Tax Expected to be Reclassed to Net Income During the Next Twelve Months AOCI Gain (Loss) Net of Tax Expected to be Reclassed to Net Income During the Next Twelve Months (in millions) AEP Texas $ (4.1 ) $ (1.1 ) $ (4.4 ) $ (1.1 ) APCo 1.6 0.9 1.8 0.9 I&M (11.1 ) (1.6 ) (11.5 ) (1.6 ) OPCo 0.7 0.6 1.0 1.0 PSO 1.9 1.0 2.1 1.0 SWEPCo (2.9 ) (1.5 ) (3.3 ) (1.5 )
Liabilities Subject to Cross Default Provisions	March 31, 2019 Liabilities for Additional Contracts with Cross Settlement Default Provisions Liability if Cross Prior to Contractual Amount of Cash Default Provision Company Netting Arrangements Collateral Posted is Triggered (in millions) AEP $ 219.2 $ 3.8 $ 189.0 APCo 1.4 — 0.1 I&M 0.8 — 0.1 SWEPCo 2.0 — 1.9 December 31, 2018 Liabilities for Additional Contracts with Cross Settlement Default Provisions Liability if Cross Prior to Contractual Amount of Cash Default Provision Company Netting Arrangements Collateral Posted is Triggered (in millions) AEP $ 225.5 $ 1.8 $ 181.0 APCo 0.9 — — I&M 0.5 — — SWEPCo 2.3 — 2.3

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Book Values and Fair Values of Long-term Debt	March 31, 2019 December 31, 2018 Company Book Value Fair Value Book Value Fair Value (in millions) AEP (a) $ 24,426.7 $ 26,225.6 $ 23,346.7 $ 24,093.9 AEP Texas 3,778.3 3,973.4 3,881.3 3,964.6 AEPTCo 2,823.4 2,949.6 2,823.0 2,782.4 APCo 4,444.0 5,040.6 4,062.6 4,473.3 I&M 3,011.4 3,201.8 3,035.4 3,070.2 OPCo 1,693.6 1,989.2 1,716.6 1,919.7 PSO 1,386.2 1,503.6 1,287.0 1,361.9 SWEPCo 2,659.1 2,763.0 2,713.4 2,670.2 (a) The fair value amount includes debt related to AEP’s Equity Units issued in March 2019 and has a fair value of $828 million as of March 31, 2019
Other Temporary Investments	March 31, 2019 Other Temporary Investments Cost Gross Gains Gross Losses Fair Value (in millions) Restricted Cash and Other Cash Deposits (a) $ 159.6 $ — $ — $ 159.6 Fixed Income Securities – Mutual Funds (b) 107.2 — (1.3 ) 105.9 Equity Securities – Mutual Funds 22.5 16.3 — 38.8 Total Other Temporary Investments $ 289.3 $ 16.3 $ (1.3 ) $ 304.3 December 31, 2018 Other Temporary Investments Cost Gross Gains Gross Losses Fair Value (in millions) Restricted Cash and Other Cash Deposits (a) $ 230.6 $ — $ — $ 230.6 Fixed Income Securities – Mutual Funds (b) 106.6 — (2.3 ) 104.3 Equity Securities – Mutual Funds 17.8 16.4 — 34.2 Total Other Temporary Investments $ 355.0 $ 16.4 $ (2.3 ) $ 369.1 (a) Primarily represents amounts held for the repayment of debt. (b)
Debt and Equity Securities Within Other Temporary Investments	Three Months Ended March 31, 2019 2018 (in millions) Proceeds from Investment Sales $ — $ — Purchases of Investments 0.1 0.6 Gross Realized Gains on Investment Sales — — Gross Realized Losses on Investment Sales — —
Nuclear Trust Fund Investments	March 31, 2019 December 31, 2018 Fair Value Gross Unrealized Gains Other-Than-Temporary Impairments Fair Value Gross Unrealized Gains Other-Than-Temporary Impairments (in millions) Cash and Cash Equivalents $ 17.4 $ — $ — $ 22.5 $ — $ — Fixed Income Securities: United States Government 1,015.6 44.0 (6.7 ) 996.1 26.7 (7.1 ) Corporate Debt 54.2 2.9 (1.8 ) 52.4 1.1 (1.9 ) State and Local Government 8.7 0.7 (0.2 ) 8.6 0.6 (0.2 ) Subtotal Fixed Income Securities 1,078.5 47.6 (8.7 ) 1,057.1 28.4 (9.2 ) Equity Securities – Domestic (a) 1,588.1 945.6 — 1,395.3 766.3 — Spent Nuclear Fuel and Decommissioning Trusts $ 2,684.0 $ 993.2 $ (8.7 ) $ 2,474.9 $ 794.7 $ (9.2 ) (a) Amount reported as Gross Unrealized Gains includes unrealized gains of $955 million and $784 million and unrealized losses of $9 million and $18 million as of March 31, 2019 and December 31, 2018
Securities Activity Within the Decommissioning and SNF Trusts	Three Months Ended March 31, 2019 2018 (in millions) Proceeds from Investment Sales $ 111.9 $ 508.6 Purchases of Investments 130.3 525.3 Gross Realized Gains on Investment Sales 12.3 12.0 Gross Realized Losses on Investment Sales 13.8 10.9
Contractual Maturities, Fair Value of Debt Securities	Fair Value of Fixed Income Securities (in millions) Within 1 year $ 356.4 After 1 year through 5 years 375.4 After 5 years through 10 years 172.8 After 10 years 173.9 Total $ 1,078.5
Fair Value, Assets and Liabilities Measured on Recurring Basis	AEP Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Other Temporary Investments Restricted Cash and Other Cash Deposits (a) $ 147.1 $ — $ — $ 12.5 $ 159.6 Fixed Income Securities – Mutual Funds 105.9 — — — 105.9 Equity Securities – Mutual Funds (b) 38.8 — — — 38.8 Total Other Temporary Investments 291.8 — — 12.5 304.3 Risk Management Assets Risk Management Commodity Contracts (c) (d) 2.5 200.4 276.6 (155.4 ) 324.1 Cash Flow Hedges: Commodity Hedges (c) — 14.8 5.5 (0.1 ) 20.2 Total Risk Management Assets 2.5 215.2 282.1 (155.5 ) 344.3 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 9.3 — — 8.1 17.4 Fixed Income Securities: United States Government — 1,015.6 — — 1,015.6 Corporate Debt — 54.2 — — 54.2 State and Local Government — 8.7 — — 8.7 Subtotal Fixed Income Securities — 1,078.5 — — 1,078.5 Equity Securities – Domestic (b) 1,588.1 — — — 1,588.1 Total Spent Nuclear Fuel and Decommissioning Trusts 1,597.4 1,078.5 — 8.1 2,684.0 Total Assets $ 1,891.7 $ 1,293.7 $ 282.1 $ (134.9 ) $ 3,332.6 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (d) $ 2.7 $ 204.8 $ 197.2 $ (155.7 ) $ 249.0 Cash Flow Hedges: Commodity Hedges (c) — 29.3 46.8 (0.1 ) 76.0 Fair Value Hedges — 6.3 — — 6.3 Total Risk Management Liabilities $ 2.7 $ 240.4 $ 244.0 $ (155.8 ) $ 331.3 AEP Assets and Liabilities Measured at Fair Value on a Recurring Basis December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Other Temporary Investments Restricted Cash and Other Cash Deposits (a) $ 221.5 $ — $ — $ 9.1 $ 230.6 Fixed Income Securities – Mutual Funds 104.3 — — — 104.3 Equity Securities – Mutual Funds (b) 34.2 — — — 34.2 Total Other Temporary Investments 360.0 — — 9.1 369.1 Risk Management Assets Risk Management Commodity Contracts (c) (f) 3.8 326.5 340.9 (288.5 ) 382.7 Cash Flow Hedges: Commodity Hedges (c) — 24.1 12.7 (2.7 ) 34.1 Total Risk Management Assets 3.8 350.6 353.6 (291.2 ) 416.8 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 12.3 — — 10.2 22.5 Fixed Income Securities: United States Government — 996.1 — — 996.1 Corporate Debt — 52.4 — — 52.4 State and Local Government — 8.6 — — 8.6 Subtotal Fixed Income Securities — 1,057.1 — — 1,057.1 Equity Securities – Domestic (b) 1,395.3 — — — 1,395.3 Total Spent Nuclear Fuel and Decommissioning Trusts 1,407.6 1,057.1 — 10.2 2,474.9 Total Assets $ 1,771.4 $ 1,407.7 $ 353.6 $ (271.9 ) $ 3,260.8 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (f) $ 4.2 $ 327.0 $ 185.6 $ (274.7 ) $ 242.1 Cash Flow Hedges: Commodity Hedges (c) — 24.8 36.8 (2.7 ) 58.9 Fair Value Hedges — 17.4 — — 17.4 Total Risk Management Liabilities $ 4.2 $ 369.2 $ 222.4 $ (277.4 ) $ 318.4 AEP Texas Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 100.6 $ — $ — $ — $ 100.6 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) $ — $ 0.2 $ — $ — $ 0.2 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 156.7 $ — $ — $ — $ 156.7 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) $ — $ 0.7 $ — $ (0.5 ) $ 0.2 APCo Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 18.3 $ — $ — $ — $ 18.3 Risk Management Assets Risk Management Commodity Contracts (c) (g) 0.2 26.8 13.4 (27.2 ) 13.2 Total Assets $ 18.5 $ 26.8 $ 13.4 $ (27.2 ) $ 31.5 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.2 $ 27.0 $ 6.0 $ (26.9 ) $ 6.3 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 25.6 $ — $ — $ — $ 25.6 Risk Management Assets Risk Management Commodity Contracts (c) (g) 0.1 59.1 58.3 (59.4 ) 58.1 Total Assets $ 25.7 $ 59.1 $ 58.3 $ (59.4 ) $ 83.7 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.2 $ 58.4 $ 0.5 $ (58.5 ) $ 0.6 I&M Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ 16.7 $ 5.2 $ (17.4 ) $ 4.5 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 9.3 — — 8.1 17.4 Fixed Income Securities: United States Government — 1,015.6 — — 1,015.6 Corporate Debt — 54.2 — — 54.2 State and Local Government — 8.7 — — 8.7 Subtotal Fixed Income Securities — 1,078.5 — — 1,078.5 Equity Securities - Domestic (b) 1,588.1 — — — 1,588.1 Total Spent Nuclear Fuel and Decommissioning Trusts 1,597.4 1,078.5 — 8.1 2,684.0 Total Assets $ 1,597.4 $ 1,095.2 $ 5.2 $ (9.3 ) $ 2,688.5 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.1 $ 16.5 $ 0.8 $ (17.0 ) $ 0.4 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ 42.1 $ 10.3 $ (43.2 ) $ 9.2 Spent Nuclear Fuel and Decommissioning Trusts Cash and Cash Equivalents (e) 12.3 — — 10.2 22.5 Fixed Income Securities: United States Government — 996.1 — — 996.1 Corporate Debt — 52.4 — — 52.4 State and Local Government — 8.6 — — 8.6 Subtotal Fixed Income Securities — 1,057.1 — — 1,057.1 Equity Securities - Domestic (b) 1,395.3 — — — 1,395.3 Total Spent Nuclear Fuel and Decommissioning Trusts 1,407.6 1,057.1 — 10.2 2,474.9 Total Assets $ 1,407.6 $ 1,099.2 $ 10.3 $ (33.0 ) $ 2,484.1 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ 0.1 $ 41.2 $ 1.4 $ (42.3 ) $ 0.4 OPCo Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 16.5 $ — $ — $ — $ 16.5 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.2 $ 106.1 $ — $ 106.3 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Restricted Cash for Securitized Funding $ 27.6 $ — $ — $ — $ 27.6 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.8 $ 99.4 $ (0.6 ) $ 99.6 PSO Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 5.4 $ (0.4 ) $ 5.0 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.1 $ 1.0 $ (0.4 ) $ 0.7 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 10.8 $ (0.4 ) $ 10.4 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.3 $ 1.3 $ (0.6 ) $ 1.0 SWEPCo Assets and Liabilities Measured at Fair Value on a Recurring Basis March 31, 2019 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 2.3 $ (0.3 ) $ 2.0 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.1 $ 2.3 $ (0.3 ) $ 2.1 December 31, 2018 Level 1 Level 2 Level 3 Other Total Assets: (in millions) Risk Management Assets Risk Management Commodity Contracts (c) (g) $ — $ — $ 5.6 $ (0.8 ) $ 4.8 Liabilities: Risk Management Liabilities Risk Management Commodity Contracts (c) (g) $ — $ 0.4 $ 3.3 $ (1.1 ) $ 2.6 (a) Amounts in “Other’’ column primarily represent cash deposits in bank accounts with financial institutions or third-parties. Level 1 and Level 2 amounts primarily represent investments in money market funds. (b) Amounts represent publicly traded equity securities and equity-based mutual funds. (c) Amounts in “Other’’ column primarily represent counterparty netting of risk management and hedging contracts and associated cash collateral under the accounting guidance for “Derivatives and Hedging.” (d) The March 31, 2019 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(7) million in 2019, $2 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $27 million in 2019, $42 million in periods 2020-2022, $23 million in periods 2023-2024 and $(13) million in periods 2025-2032. Risk management commodity contracts are substantially comprised of power contracts. (e) Amounts in “Other’’ column primarily represent accrued interest receivables from financial institutions. Level 1 amounts primarily represent investments in money market funds. (f) The December 31, 2018 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(4) million in 2019, $1 million in periods 2020-2022, $1 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $108 million in 2019, $37 million in periods 2020-2022, $23 million in periods 2023-2024 and $(12) million in periods 2025-2032. Risk management commodity contracts are substantially comprised of power contracts. (g)
Changes in Fair Value of Net Trading Derivatives Classified as Level 3	Three Months Ended March 31, 2019 AEP APCo I&M OPCo PSO SWEPCo (in millions) Balance as of December 31, 2018 $ 131.2 $ 57.8 $ 8.9 $ (99.4 ) $ 9.5 $ 2.3 Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) (a) (b) (23.0 ) (29.0 ) — (0.4 ) 6.8 3.3 Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date (a) 8.5 — — — — — Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income (15.8 ) — — — — — Settlements (54.5 ) (17.8 ) (5.1 ) 1.8 (13.0 ) (7.3 ) Transfers into Level 3 (c) (d) 0.1 — — — — — Transfers out of Level 3 (d) (1.2 ) (0.7 ) (0.4 ) — — — Changes in Fair Value Allocated to Regulated Jurisdictions (e) (7.2 ) (2.9 ) 1.0 (8.1 ) 1.1 1.7 Balance as of March 31, 2019 $ 38.1 $ 7.4 $ 4.4 $ (106.1 ) $ 4.4 $ — Three Months Ended March 31, 2018 AEP APCo I&M OPCo PSO SWEPCo (in millions) Balance as of December 31, 2017 $ 40.3 $ 24.7 $ 7.6 $ (132.4 ) $ 6.2 $ 5.9 Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) (a) (b) 97.3 68.1 3.0 0.3 11.4 0.6 Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date (a) 2.0 — — — — — Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income 17.9 — — — — — Settlements (129.8 ) (85.4 ) (7.4 ) 1.1 (16.1 ) (3.9 ) Transfers into Level 3 (c) (d) 2.1 — — — — — Transfers out of Level 3 (d) (2.0 ) — (0.3 ) — — — Changes in Fair Value Allocated to Regulated Jurisdictions (e) 34.2 1.7 — 32.5 1.3 (1.7 ) Balance as of March 31, 2018 $ 62.0 $ 9.1 $ 2.9 $ (98.5 ) $ 2.8 $ 0.9 (a) Included in revenues on the statements of income. (b) Represents the change in fair value between the beginning of the reporting period and the settlement of the risk management commodity contract. (c) Represents existing assets or liabilities that were previously categorized as Level 2. (d) Transfers are recognized based on their value at the beginning of the reporting period that the transfer occurred. (e)
Significant Unobservable Inputs for Level 3	Significant Unobservable Inputs March 31, 2019 AEP Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Energy Contracts $ 256.7 $ 229.0 Discounted Cash Flow Forward Market Price (a) $ (0.05 ) $ 165.64 $ 32.60 Natural Gas Contracts — 2.0 Discounted Cash Flow Forward Market Price (b) 2.27 2.87 2.48 FTRs 25.4 13.0 Discounted Cash Flow Forward Market Price (a) (8.34 ) 10.30 (0.02 ) Total $ 282.1 $ 244.0 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Energy Contracts $ 257.1 $ 212.5 Discounted Cash Flow Forward Market Price (a) $ (0.05 ) $ 176.57 $ 33.07 Natural Gas Contracts — 2.5 Discounted Cash Flow Forward Market Price (b) 2.18 3.54 2.47 FTRs 96.5 7.4 Discounted Cash Flow Forward Market Price (a) (11.68 ) 17.79 1.09 Total $ 353.6 $ 222.4 Significant Unobservable Inputs March 31, 2019 APCo Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 3.6 $ 0.4 Discounted Cash Flow Forward Market Price $ 17.40 $ 49.25 $ 34.91 FTRs 9.8 5.6 Discounted Cash Flow Forward Market Price (0.06 ) 2.44 0.61 Total $ 13.4 $ 6.0 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 2.4 $ 0.5 Discounted Cash Flow Forward Market Price $ 16.82 $ 62.65 $ 37.00 FTRs 55.9 — Discounted Cash Flow Forward Market Price 0.10 15.16 3.27 Total $ 58.3 $ 0.5 Significant Unobservable Inputs March 31, 2019 I&M Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 1.9 $ 0.3 Discounted Cash Flow Forward Market Price $ 17.40 $ 49.25 $ 34.91 FTRs 3.3 0.5 Discounted Cash Flow Forward Market Price (0.10 ) 2.02 0.86 Total $ 5.2 $ 0.8 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ 1.4 $ 0.9 Discounted Cash Flow Forward Market Price $ 16.82 $ 62.65 $ 37.00 FTRs 8.9 0.5 Discounted Cash Flow Forward Market Price (2.11 ) 6.21 1.06 Total $ 10.3 $ 1.4 Significant Unobservable Inputs March 31, 2019 OPCo Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ — $ 106.1 Discounted Cash Flow Forward Market Price $ 25.35 $ 66.99 $ 43.29 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) Energy Contracts $ — $ 99.4 Discounted Cash Flow Forward Market Price $ 26.29 $ 62.74 $ 42.50 Significant Unobservable Inputs March 31, 2019 PSO Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) FTRs $ 5.4 $ 1.0 Discounted Cash Flow Forward Market Price $ (8.34 ) $ 10.30 $ (1.09 ) December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input (a) Low High Average (in millions) FTRs $ 10.8 $ 1.3 Discounted Cash Flow Forward Market Price $ (11.68 ) $ 10.30 $ (1.40 ) Significant Unobservable Inputs March 31, 2019 SWEPCo Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Natural Gas Contracts $ — $ 2.0 Discounted Cash Flow Forward Market Price (b) $ 2.27 $ 2.87 $ 2.48 FTRs 2.3 0.3 Discounted Cash Flow Forward Market Price (a) (8.34 ) 10.30 (1.09 ) Total $ 2.3 $ 2.3 December 31, 2018 Significant Input/Range Fair Value Valuation Unobservable Weighted Assets Liabilities Technique Input Low High Average (in millions) Natural Gas Contracts $ — $ 2.5 Discounted Cash Flow Forward Market Price (b) $ 2.18 $ 3.54 $ 2.47 FTRs 5.6 0.8 Discounted Cash Flow Forward Market Price (a) (11.68 ) 10.30 (1.40 ) Total $ 5.6 $ 3.3 (a) Represents market prices in dollars per MWh. (b)
Sensitivity of Fair Value Measurements	Sensitivity of Fair Value Measurements Significant Unobservable Input Position Change in Input Impact on Fair Value Measurement Forward Market Price Buy Increase (Decrease) Higher (Lower) Forward Market Price Sell Increase (Decrease) Lower (Higher)

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2019
Status of Tax Reform Regulatory Proceedings	Registrant (Jurisdiction) Change in Tax Rate Excess ADIT Subject to Normalization Requirements Excess ADIT Not Subject to Normalization Requirements AEP Texas (Texas-Distribution) Order Issued Order Issued Order Issued – Partial (a) AEP Texas (Texas-Transmission) Order Issued To be addressed in a later filing To be addressed in a later filing I&M (Michigan) Order Issued Case Pending Case Pending SWEPCo (Louisiana) Case Pending – Rates Implemented (b) Case Pending – Rates Implemented (b) Case Pending – Rates Implemented (b) SWEPCo (Texas) Order Issued To be addressed in a later filing To be addressed in a later filing PJM FERC Transmission Settlement Approved (c) Settlement Approved (c) Settlement Approved (c) SPP FERC Transmission Settlement Pending Settlement Pending Settlement Pending (a) A portion of the Excess ADIT that is not subject to rate normalization requirements is to be addressed in a later filing. (b) Rates have been implemented through a filed formula rate plan that is subject to true-up and final commission approval. (c)
Schedule of Effective Income Tax Rate Reconciliation	Three Months Ended Company 2019 2018 AEP 7.2 % 18.3 % AEP Texas 10.4 % 16.3 % AEPTCo 20.9 % 20.7 % APCo (22.0 )% 18.2 % I&M (2.8 )% 16.2 % OPCo 13.4 % 20.5 % PSO 0.6 % 16.3 % SWEPCo 2.4 % 18.4 %

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Lease Rental Costs	Three Months Ended March 31, 2019 AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Operating Lease Cost $ 64.6 $ 3.8 $ 0.6 $ 4.6 $ 23.0 $ 3.6 $ 1.5 $ 1.8 Finance Lease Cost: Amortization of Right-of-Use Assets 14.2 1.1 — 1.5 1.3 0.7 0.7 2.7 Interest on Lease Liabilities 4.1 0.3 — 0.7 0.8 0.2 0.1 0.8 Total Lease Rental Costs (a) $ 82.9 $ 5.2 $ 0.6 $ 6.8 $ 25.1 $ 4.5 $ 2.3 $ 5.3 (a)
Supplemental Balance Sheet Information Related to Leases	Lease Term and Discount Rate AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo Weighted-Average Remaining Lease Term (years): Operating Leases 5.43 7.30 2.71 6.34 4.32 8.21 7.11 6.67 Finance Leases 5.94 7.07 1.08 6.44 6.91 6.16 6.06 5.60 Weighted-Average Discount Rate: Operating Leases 3.61 % 3.82 % 3.14 % 3.66 % 3.45 % 3.86 % 3.67 % 3.89 % Finance Leases 6.19 % 4.79 % 9.33 % 8.61 % 9.03 % 4.81 % 4.78 % 5.04 % AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Cash paid for amounts included in the measurement of lease liabilities: Operating Cash Flows from Operating Leases $ 28.9 $ 3.8 $ 0.7 $ 4.2 $ 5.0 $ 3.6 $ 1.5 $ 1.4 Operating Cash Flows from Finance Leases 3.8 0.3 — 0.7 0.7 0.2 0.1 0.7 Financing Cash Flows from Finance Leases 14.3 1.2 — 1.6 1.2 0.7 0.7 2.7 Non-cash Acquisitions Under Operating Leases $ 38.5 $ 4.6 $ — $ 3.5 $ 2.6 $ 15.8 $ 2.3 $ 2.6
Property, Plant and Equipment and Related Obligations Under Finance Leases	March 31, 2019 AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Property, Plant and Equipment Under Finance Leases: Generation $ 166.3 $ — $ — $ 38.6 $ 27.0 $ — $ 2.6 $ 69.4 Other Property, Plant and Equipment 277.3 39.9 0.2 17.4 33.4 21.3 18.3 11.7 Total Property, Plant and Equipment 443.6 39.9 0.2 56.0 60.4 21.3 20.9 81.1 Accumulated Amortization 149.4 10.1 0.1 15.7 21.2 6.7 8.1 22.1 Net Property, Plant and Equipment Under Finance Leases $ 294.2 $ 29.8 $ 0.1 $ 40.3 $ 39.2 $ 14.6 $ 12.8 $ 59.0 Obligations Under Finance Leases: Noncurrent Liability $ 237.4 $ 24.9 $ — $ 34.0 $ 33.7 $ 11.4 $ 9.8 $ 49.3 Liability Due Within One Year 61.5 4.9 0.1 6.3 5.5 3.2 3.0 10.6 Total Obligations Under Finance Leases $ 298.9 $ 29.8 $ 0.1 $ 40.3 $ 39.2 $ 14.6 $ 12.8 $ 59.9
Operating Lease Assets and Related Obligations	March 31, 2019 AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Operating Lease Assets $ 1,045.4 $ 82.4 $ 5.8 $ 79.1 $ 326.3 $ 86.6 $ 34.8 $ 38.0 Obligations Under Operating Leases: Noncurrent Liability $ 860.2 $ 70.2 $ 3.2 $ 64.8 $ 266.0 $ 74.0 $ 29.1 $ 32.3 Liability Due Within One Year 228.2 12.2 2.6 15.0 81.8 13.0 5.7 6.1 Total Obligations Under Operating Leases $ 1,088.4 $ 82.4 $ 5.8 $ 79.8 $ 347.8 $ 87.0 $ 34.8 $ 38.4
Finance Lease Liabilities Rolling Future Minimum Lease Payments	Finance Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Year 1 $ 74.1 $ 6.2 $ 0.1 $ 9.2 $ 8.4 $ 3.8 $ 3.6 $ 13.2 Year 2 63.6 5.8 — 8.4 7.5 3.3 2.9 11.3 Year 3 54.9 5.1 — 7.6 6.9 2.7 2.1 10.5 Year 4 46.2 4.5 — 7.1 6.3 2.0 1.7 9.3 Year 5 38.8 3.9 — 6.6 5.9 1.5 1.4 9.3 Later Years 87.4 10.2 — 12.3 20.9 4.0 3.3 15.7 Total Future Minimum Lease Payments 365.0 35.7 0.1 51.2 55.9 17.3 15.0 69.3 Less Imputed Interest 66.1 5.9 — 10.9 16.7 2.7 2.2 9.4 Estimated Present Value of Future Minimum Lease Payments $ 298.9 $ 29.8 $ 0.1 $ 40.3 $ 39.2 $ 14.6 $ 12.8 $ 59.9
Operating Lease Liabilities Rolling Future Minimum Lease Payments	Noncancelable Operating Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Year 1 $ 263.3 $ 15.2 $ 2.7 $ 18.0 $ 92.5 $ 16.0 $ 6.8 $ 7.6 Year 2 253.3 14.4 2.0 16.5 89.5 14.4 6.4 7.4 Year 3 235.9 13.5 0.9 14.0 84.9 12.4 5.4 6.9 Year 4 226.8 12.5 0.6 12.8 85.2 11.6 5.1 6.4 Year 5 61.5 11.1 — 9.7 7.0 10.2 4.6 5.2 Later Years 180.7 29.4 — 20.5 20.4 38.6 12.1 11.1 Total Future Minimum Lease Payments 1,221.5 96.1 6.2 91.5 379.5 103.2 40.4 44.6 Less Imputed Interest 133.1 13.7 0.4 11.7 31.7 16.2 5.6 6.2 Estimated Present Value of Future Minimum Lease Payments $ 1,088.4 $ 82.4 $ 5.8 $ 79.8 $ 347.8 $ 87.0 $ 34.8 $ 38.4
Future Minimum Lease Payments	Finance Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) 2019 $ 70.8 $ 5.8 $ 0.1 $ 9.0 $ 8.2 $ 3.3 $ 3.4 $ 13.1 2020 60.2 5.3 — 8.0 7.2 2.7 2.6 11.5 2021 51.7 4.7 — 7.3 6.6 2.3 2.0 10.5 2022 43.8 4.2 — 6.8 6.1 1.7 1.6 9.4 2023 35.5 3.7 — 6.3 5.7 1.2 1.4 8.6 Later Years 90.2 10.1 — 13.3 21.7 2.8 3.3 18.7 Total Future Minimum Lease Payments 352.2 33.8 0.1 50.7 55.5 14.0 14.3 71.8 Less Imputed Interest 63.2 5.3 — 10.9 16.8 1.9 2.0 11.0 Estimated Present Value of Future Minimum Lease Payments $ 289.0 $ 28.5 $ 0.1 $ 39.8 $ 38.7 $ 12.1 $ 12.3 $ 60.8 Noncancelable Operating Leases AEP AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) 2019 $ 259.6 $ 15.1 $ 2.3 $ 17.6 $ 92.6 $ 14.5 $ 6.5 $ 7.4 2020 250.1 14.1 1.8 16.5 89.3 13.2 6.0 7.2 2021 232.7 13.2 1.0 13.9 84.8 10.9 5.0 6.7 2022 222.5 12.2 0.5 12.8 83.8 10.0 4.6 6.1 2023 58.3 10.8 0.1 9.9 6.5 8.8 4.1 5.0 Later Years 165.2 28.4 — 20.5 19.5 31.7 10.7 11.7 Total Future Minimum Lease Payments $ 1,188.4 $ 93.8 $ 5.7 $ 91.2 $ 376.5 $ 89.1 $ 36.9 $ 44.1
Maximum Potential Loss	Company Maximum Potential Loss (in millions) AEP $ 48.8 AEP Texas 10.9 APCo 8.9 I&M 3.9 OPCo 8.4 PSO 4.0 SWEPCo 4.4
Future Minimum Lease Payments	Future Minimum Lease Payments AEP (a) I&M (in millions) 2019 $ 147.8 $ 73.9 2020 147.8 73.9 2021 147.8 73.9 2022 147.2 73.6 Total Future Minimum Lease Payments $ 590.6 $ 295.3 (a)

Financing Activities (Tables)

Financing Activities (Tables)	3 Months Ended
	Mar. 31, 2019
Long-term Debt	Type of Debt March 31, 2019 December 31, 2018 (in millions) Senior Unsecured Notes $ 19,411.6 $ 18,903.3 Pollution Control Bonds 1,590.0 1,643.8 Notes Payable 177.0 204.7 Securitization Bonds 973.0 1,111.4 Spent Nuclear Fuel Obligation (a) 275.3 273.6 Junior Subordinated Notes (b) 785.0 — Other Long-term Debt 1,214.8 1,209.9 Total Long-term Debt Outstanding 24,426.7 23,346.7 Long-term Debt Due Within One Year 1,528.5 1,698.5 Long-term Debt $ 22,898.2 $ 21,648.2 (a) Pursuant to the Nuclear Waste Policy Act of 1982, I&M, a nuclear licensee, has an obligation to the United States Department of Energy for SNF disposal. The obligation includes a one-time fee for nuclear fuel consumed prior to April 7, 1983. Trust fund assets related to this obligation were $318 million and $317 million as of March 31, 2019 and December 31, 2018 , respectively, and are included in Spent Nuclear Fuel and Decommissioning Trusts on the balance sheets. (b) See “Equity Units” section below for additional information.
Long-term Debt Issuances	Company Type of Debt Principal Amount (a) Interest Rate Due Date Issuances: (in millions) (%) AEP Junior Subordinated Notes (b) $ 805.0 3.40 2024 APCo Senior Unsecured Notes 400.0 4.50 2049 PSO Senior Unsecured Notes 100.0 3.91 2029 Non-Registrant: Transource Energy Other Long-term Debt 6.3 Variable 2020 Total Issuances $ 1,311.3 (a) Amounts indicated on the statements of cash flows are net of issuance costs and premium or discount and will not tie to the issuance amounts. (b)
Retirements and Principal Payments	Company Type of Debt Principal Amount Paid Interest Rate Due Date Retirements and Principal Payments: (in millions) (%) AEP Texas Securitization Bonds $ 103.5 5.31 2020 APCo Securitization Bonds 12.0 2.01 2023 I&M Notes Payable 1.4 Variable 2019 I&M Notes Payable 1.4 Variable 2019 I&M Notes Payable 7.1 Variable 2020 I&M Notes Payable 5.9 Variable 2021 I&M Notes Payable 5.0 Variable 2022 I&M Notes Payable 5.3 Variable 2022 I&M Other Long-term Debt 0.4 6.00 2025 OPCo Securitization Bonds 23.4 2.05 2019 PSO Other Long-term Debt 0.1 3.00 2027 SWEPCo Pollution Control Bonds 53.5 1.60 2019 SWEPCo Notes Payable 1.6 4.58 2032 Total Retirements and Principal Payments $ 220.6
Utility Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits	Company Maximum Borrowings from the Utility Money Pool Maximum Loans to the Utility Money Pool Average Borrowings from the Utility Money Pool Average Loans to the Utility Money Pool Net Loans to Authorized Short-term Borrowing Limit (in millions) AEP Texas $ 379.9 $ — $ 301.9 $ — $ (271.2 ) $ 500.0 AEPTCo 279.0 80.0 165.3 32.2 (191.1 ) 795.0 (a) APCo 225.4 232.2 189.3 75.9 216.6 600.0 I&M 46.3 66.0 19.0 23.2 (21.9 ) 500.0 OPCo 238.1 — 156.9 — (227.6 ) 500.0 PSO 140.5 — 89.1 — (55.2 ) 300.0 SWEPCo 100.6 81.4 41.9 24.0 (74.0 ) 350.0 (a) Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions.
Nonutility Money Pool Activity [Table Text Block]	Maximum Loans Average Loans Loans to the Nonutility to the Nonutility to the Nonutility Money Pool as of Company Money Pool Money Pool March 31, 2019 (in millions) AEP Texas $ 8.0 $ 7.7 $ 7.7 SWEPCo 2.0 2.0 2.0
Direct Borrowing Activity [Table Text Block]	Authorized Maximum Maximum Average Average Borrowings from Loans to Short-term Borrowings Loans Borrowings Loans AEP as of AEP as of Borrowing from AEP to AEP from AEP to AEP March 31, 2019 March 31, 2019 Limit (in millions) $ 1.3 $ 117.6 $ 1.2 $ 61.8 $ 1.2 $ 42.7 $ 75.0 (a) (a)
Maximum and Minimum Interest Rates for Funds Either Borrowed from or Loaned to Utility Money Pool	Three Months Ended March 31, 2019 2018 Maximum Interest Rate 3.02 % 2.42 % Minimum Interest Rate 2.73 % 1.83 %
Average Interest Rates for Funds Borrowed from and Loaned to Utility Money Pool	Average Interest Rate for Funds Average Interest Rate for Funds Borrowed from the Utility Money Pool Loaned to the Utility Money Pool for Three Months Ended March 31, for Three Months Ended March 31, Company 2019 2018 2019 2018 AEP Texas 2.86 % 2.07 % — % 1.90 % AEPTCo 2.83 % 2.06 % 2.90 % 1.92 % APCo 2.92 % 2.00 % 2.79 % 2.00 % I&M 2.80 % 2.02 % 2.87 % 2.00 % OPCo 2.85 % 2.00 % — % 2.40 % PSO 2.89 % 2.01 % — % — % SWEPCo 2.81 % 2.10 % 2.97 % 1.88 %
Maximum Minimum Average Interest Rates for Funds Borrowed from Loaned to Nonutility Money Pool [Text Block]	Three Months Ended March 31, 2019 Three Months Ended March 31, 2018 Maximum Minimum Average Maximum Minimum Average Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate for Funds for Funds for Funds for Funds for Funds for Funds Loaned to Loaned to Loaned to Loaned to Loaned to Loaned to the Nonutility the Nonutility the Nonutility the Nonutility the Nonutility the Nonutility Company Money Pool Money Pool Money Pool Money Pool Money Pool Money Pool AEP Texas 3.02 % 2.73 % 2.87 % 2.42 % 1.83 % 2.00 % SWEPCo 3.02 % 2.73 % 2.87 % 2.42 % 1.83 % 2.00 %
Maximum Minimum and Average Interest Rates for Funds Borrowed from and Loaned to AEP [Table Text Block]	Maximum Minimum Maximum Minimum Average Average Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate Interest Rate Three Months for Funds for Funds for Funds for Funds for Funds for Funds Ended Borrowed Borrowed Loaned Loaned Borrowed Loaned March 31, from AEP from AEP to AEP to AEP from AEP to AEP 2019 3.02 % 2.73 % 3.02 % 2.73 % 2.87 % 2.86 % 2018 2.42 % 1.83 % 2.42 % 1.83 % 2.00 % 2.02 %
Short Term Debt	March 31, 2019 December 31, 2018 Type of Debt Outstanding Amount Interest Rate (a) Outstanding Interest (dollars in millions) Securitized Debt for Receivables (b) $ 750.0 2.71 % $ 750.0 2.16 % Commercial Paper 1,108.0 2.75 % 1,160.0 2.96 % Total Short-term Debt $ 1,858.0 $ 1,910.0 (a) Weighted-average rate. (b)
Comparative Accounts Receivable Information	Three Months Ended March 31, 2019 2018 (dollars in millions) Effective Interest Rates on Securitization of Accounts Receivable 2.71 % 1.74 % Net Uncollectible Accounts Receivable Written-Off $ 6.4 $ 4.2
Customer Accounts Receivable Managed Portfolio	March 31, 2019 December 31, 2018 (in millions) Accounts Receivable Retained Interest and Pledged as Collateral Less Uncollectible Accounts $ 941.4 $ 972.5 Short-term – Securitized Debt of Receivables 750.0 750.0 Delinquent Securitized Accounts Receivable 52.7 50.3 Bad Debt Reserves Related to Securitization 29.1 27.5 Unbilled Receivables Related to Securitization 230.3 281.4
Accounts Receivable and Accrued Unbilled Revenues	Company March 31, 2019 December 31, 2018 (in millions) APCo $ 132.4 $ 133.3 I&M 165.4 152.9 OPCo 383.8 395.2 PSO 103.2 109.7 SWEPCo 129.1 150.3
Fees Paid to AEP Credit for Customer Accounts Receivable Sold	Three Months Ended March 31, Company 2019 2018 (in millions) APCo $ 2.2 $ 1.7 I&M 2.8 2.1 OPCo 7.8 5.6 PSO 2.1 1.8 SWEPCo 2.6 1.9
Proceeds on Sale of Receivables to AEP Credit	Three Months Ended March 31, Company 2019 2018 (in millions) APCo $ 374.4 $ 400.2 I&M 478.6 459.1 OPCo 636.8 680.0 PSO 324.5 332.6 SWEPCo 371.9 397.6

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2019
Disaggregated Revenues from Contracts with Customers	Three Months Ended March 31, 2019 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation & Marketing Corporate and Other Reconciling Adjustments AEP Consolidated (in millions) Retail Revenues: Residential Revenues $ 982.4 $ 586.1 $ — $ — $ — $ — $ 1,568.5 Commercial Revenues 511.2 310.9 — — — — 822.1 Industrial Revenues 532.1 123.9 — — — 1.8 657.8 Other Retail Revenues 43.3 11.1 — — — — 54.4 Total Retail Revenues 2,069.0 1,032.0 — — — 1.8 3,102.8 Wholesale and Competitive Retail Revenues: Generation Revenues (a) 224.7 — — 108.8 — (78.5 ) 255.0 Transmission Revenues (b) 73.5 99.6 255.1 — — (219.4 ) 208.8 Marketing, Competitive Retail and Renewable Revenues — — — 361.5 — — 361.5 Total Wholesale and Competitive Retail Revenues 298.2 99.6 255.1 470.3 — (297.9 ) 825.3 Other Revenues from Contracts with Customers (c) 39.5 46.0 3.1 2.3 23.3 (36.1 ) 78.1 Total Revenues from Contracts with Customers 2,406.7 1,177.6 258.2 472.6 23.3 (332.2 ) 4,006.2 Other Revenues: Alternative Revenues (c) (3.4 ) 5.0 (1.8 ) — — — (0.2 ) Other Revenues (c) — 39.4 — 9.2 2.2 — 50.8 Total Other Revenues (3.4 ) 44.4 (1.8 ) 9.2 2.2 — 50.6 Total Revenues $ 2,403.3 $ 1,222.0 $ 256.4 $ 481.8 $ 25.5 $ (332.2 ) $ 4,056.8 (a) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for Generation & Marketing was $37 million. The remaining affiliated amounts were immaterial. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEP Transmission Holdco was $198 million. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. Three Months Ended March 31, 2018 Vertically Integrated Utilities Transmission and Distribution Utilities AEP Transmission Holdco Generation & Marketing Corporate and Other Reconciling Adjustments AEP Consolidated (in millions) Retail Revenues: Residential Revenues $ 1,001.2 $ 567.9 $ — $ — $ — $ — $ 1,569.1 Commercial Revenues 508.0 294.1 — — — — 802.1 Industrial Revenues 526.6 118.5 — — — — 645.1 Other Retail Revenues 43.9 10.4 — — — — 54.3 Total Retail Revenues (a) 2,079.7 990.9 — — — — 3,070.6 Wholesale and Competitive Retail Revenues: Generation Revenues (b) 217.0 — — 172.2 — (30.1 ) 359.1 Transmission Revenues (c) 75.0 94.1 219.5 — — (179.8 ) 208.8 Marketing, Competitive Retail and Renewable Revenues — — — 309.7 — — 309.7 Total Wholesale and Competitive Retail Revenues 292.0 94.1 219.5 481.9 — (209.9 ) 877.6 Other Revenues from Contracts with Customers (d) 39.9 49.7 2.0 2.2 22.0 (25.1 ) 90.7 Total Revenues from Contracts with Customers 2,411.6 1,134.7 221.5 484.1 22.0 (235.0 ) 4,038.9 Other Revenues: Alternative Revenues (d) (9.1 ) 6.0 (16.0 ) — — — (19.1 ) Other Revenues (d) 5.5 21.7 — 21.0 2.0 (21.7 ) 28.5 Total Other Revenues (3.6 ) 27.7 (16.0 ) 21.0 2.0 (21.7 ) 9.4 Total Revenues $ 2,408.0 $ 1,162.4 $ 205.5 $ 505.1 $ 24.0 $ (256.7 ) $ 4,048.3 (a) 2018 amounts have been revised to reflect the reclassification of certain customer accounts between Retail classes. This reclassification did not impact previously reported Total Retail Revenues. Management concluded that these prior period disclosure only errors were immaterial individually and in the aggregate. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for Generation & Marketing was $27 million. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEP Transmission Holdco was $162 million. The remaining affiliated amounts were immaterial. (d) Three Months Ended March 31, 2019 AEP Texas AEPTCo APCo I&M OPCo PSO SWEPCo (in millions) Retail Revenues: Residential Revenues $ 120.9 $ — $ 372.5 $ 218.4 $ 471.6 $ 140.0 $ 140.1 Commercial Revenues 97.9 — 142.2 121.3 210.5 80.8 113.7 Industrial Revenues 33.0 — 147.5 138.4 89.7 71.0 81.2 Other Retail Revenues 7.3 — 19.6 1.8 3.4 18.0 2.2 Total Retail Revenues 259.1 — 681.8 479.9 775.2 309.8 337.2 Wholesale Revenues: Generation Revenues (a) — — 67.5 111.9 — 8.6 57.2 Transmission Revenues (b) 85.8 242.1 25.7 6.3 13.9 9.8 24.2 Total Wholesale Revenues 85.8 242.1 93.2 118.2 13.9 18.4 81.4 Other Revenues from Contracts with Customers (c) 6.9 3.1 13.4 21.0 39.0 5.8 7.8 Total Revenues from Contracts with Customers 351.8 245.2 788.4 619.1 828.1 334.0 426.4 Other Revenues: Alternative Revenues (d) (0.9 ) (1.7 ) 4.4 (4.8 ) 3.6 (1.2 ) (5.3 ) Other Revenues (d) 39.8 — — — 5.1 — — Total Other Revenues 38.9 (1.7 ) 4.4 (4.8 ) 8.7 (1.2 ) (5.3 ) Total Revenues $ 390.7 $ 243.5 $ 792.8 $ 614.3 $ 836.8 $ 332.8 $ 421.1 (a) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for APCo was $35 million primarily relating to the PPA with KGPCo. The remaining affiliated amounts were immaterial. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEPTCo was $195 million. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for I&M was $15 million primarily relating to the barging, urea transloading and other transportation services. The remaining affiliated amounts were immaterial. (d) Amounts include affiliated and nonaffiliated revenues. Three Months Ended March 31, 2018 AEP Texas AEPTCo (f) APCo I&M OPCo PSO SWEPCo (in millions) Retail Revenues: Residential Revenues $ 131.6 $ — $ 414.0 $ 189.0 $ 436.8 $ 141.1 $ 140.1 Commercial Revenues 99.4 — 146.6 109.6 194.5 84.3 108.3 Industrial Revenues 30.9 — 147.3 132.0 87.9 69.1 77.2 Other Retail Revenues 7.1 — 19.6 2.2 3.2 18.3 2.1 Total Retail Revenues (a) 269.0 — 727.5 432.8 722.4 312.8 327.7 Wholesale Revenues: Generation Revenues (b) — — 62.8 114.0 — 5.9 59.9 Transmission Revenues (c) 78.0 185.0 24.8 6.8 16.0 10.6 26.0 Total Wholesale Revenues 78.0 185.0 87.6 120.8 16.0 16.5 85.9 Other Revenues from Contracts with Customers (d) 7.1 2.0 11.2 22.7 42.3 4.2 6.1 Total Revenues from Contracts with Customers 354.1 187.0 826.3 576.3 780.7 333.5 419.7 Other Revenues: Alternative Revenues (e) (0.3 ) 4.7 (5.9 ) (5.0 ) 6.3 3.3 (0.3 ) Other Revenues (e) 17.8 — — 5.5 3.9 — — Total Other Revenues 17.5 4.7 (5.9 ) 0.5 10.2 3.3 (0.3 ) Total Revenues $ 371.6 $ 191.7 $ 820.4 $ 576.8 $ 790.9 $ 336.8 $ 419.4 (a) 2018 amounts have been revised to reflect the reclassification of certain customer accounts between Retail classes. This reclassification did not impact previously reported Total Retail Revenues. Management concluded that these prior period disclosure only errors were immaterial individually and in the aggregate. (b) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for APCo was $40 million primarily relating to the PPA with KGPCo. The remaining affiliated amounts were immaterial. (c) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEPTCo was $160 million. The remaining affiliated amounts were immaterial. (d) Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for I&M was $15 million primarily relating to the barging, urea transloading and other transportation services. The remaining affiliated amounts were immaterial. (e) Amounts include affiliated and nonaffiliated revenues. (f)
Fixed Performance Obligations	Company 2019 2020-2021 2022-2023 After 2023 Total (in millions) AEP $ 732.3 $ 199.1 $ 162.7 $ 285.7 $ 1,379.8 AEP Texas 278.2 — — — 278.2 AEPTCo 672.5 — — — 672.5 APCo 108.9 31.1 23.2 11.6 174.8 I&M 21.5 8.8 8.8 4.4 43.5 OPCo 47.4 — — — 47.4 PSO 13.6 — — — 13.6 SWEPCo 28.7 — — — 28.7
Affiliated Accounts Receivable Contracts with Customers [Table Text Block]	Company March 31, 2019 December 31, 2018 (in millions) AEPTCo $ 65.9 $ 58.6 APCo 46.3 52.5 I&M 24.0 35.3 OPCo 31.2 46.1 PSO 13.3 12.4 SWEPCo 10.6 16.3

Significant Accounting Matter_3

Significant Accounting Matters (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			63 Months Ended	90 Months Ended
	Mar. 31, 2019	Mar. 31, 2018		Mar. 31, 2018	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Amounts Attributable to AEP Common Shareholders
EARNINGS ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 572.8	$ 454.4
Weighted Average Number of Basic AEP Common Shares Outstanding	493,309,076	492,267,402
Total Basic Earnings Per Share Attributable to AEP Common Shareholders	$ 1.16	$ 0.92
Weighted Average Dilutive Effect of:
Weighted Average Number of Diluted AEP Common Shares Outstanding	494,484,144	493,127,300
Total Diluted Earnings Per Share Attributable to AEP Common Shareholders	$ 1.16	$ 0.92
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents	$ 227.7					$ 227.7	$ 234.1
Restricted Cash						135.4	210
Total Cash, Cash Equivalents and Restricted Cash						363.1	444.1
Total Cash, Cash Equivalents and Restricted Cash						363.1	444.1	$ 316.5	$ 412.6
Revenues
TOTAL REVENUES	4,056.8	$ 4,048.3
Expenses
Depreciation and Amortization	605.8	539.7
TOTAL EXPENSES	3,268.4	3,342.3
OPERATING INCOME (LOSS)	788.4	706
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction	28.9	30.7
Interest Expense	(255.8)	(234)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	600.1	540.2
Income Tax Expense (Benefit)	44.5	102
NET INCOME (LOSS)	574.1	456.7
Operating Activities
NET INCOME (LOSS)	574.1	456.7
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization	605.8	539.7
Deferred Income Taxes	16.8	87.3
Allowance for Equity Funds Used During Construction	(28.9)	(30.7)
Change in Other Noncurrent Assets	(47.9)	(59.8)
Change in Other Noncurrent Liabilities	67.3	133.3
Accounts Receivable, Net	57.5	39.7
Accounts Payable	(152.6)	(129.3)
Accrued Taxes, Net	(77)	(74.3)
Net Cash Flows from (Used for) Operating Activities	808.3	802.2
Investing Activities
Net Cash Flows from (Used for) Investing Activities	(1,582.8)	(1,927.8)
Financing Activities
Net Cash Flows from (Used for) Financing Activities	693.5	1,029.5
Cash and Cash Equivalents at Beginning of Period	234.1
Cash and Cash Equivalents at End of Period	227.7
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid	$ 846.3	$ 799.9
Organization and Summary of Significant Accounting Policies (Textuals)
Antidilutive Shares Outstanding	0	0
NET INCOME (LOSS)	$ 574.1	$ 456.7
Retained Earnings						9,565.6	9,325.3
Restricted Stock Units and Performance Share Units [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares	1,200,000	800,000
Dilutive Securities, Effect on Basic Earnings Per Share	$ 0	$ 0
AEP Transmission Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents	$ 0	$ 0		$ 0		0	0	0	0
Revenues
TOTAL REVENUES	243.5	191.7	[1],[2]
Expenses
Depreciation and Amortization	40.3	30.3
TOTAL EXPENSES	101.9	80.6
OPERATING INCOME (LOSS)	141.6	111.1
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction	11.3	14.9
Interest Expense	(21.7)	(20.3)	[1]
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	131.9	106.1
Income Tax Expense (Benefit)	27.6	22	[1]
NET INCOME (LOSS)	104.3	84.1	[1]
Operating Activities
NET INCOME (LOSS)	104.3	84.1	[1]
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization	40.3	30.3
Deferred Income Taxes	14.5	15.5
Allowance for Equity Funds Used During Construction	(11.3)	(14.9)
Change in Other Noncurrent Assets	2.7	2.9
Change in Other Noncurrent Liabilities	2.2	23.9
Accounts Receivable, Net	(8.2)	(9.6)
Accounts Payable	11.4	(10.7)
Accrued Taxes, Net	(32.1)	(34)
Net Cash Flows from (Used for) Operating Activities	166.2	127.1
Investing Activities
Net Cash Flows from (Used for) Investing Activities	(343.8)	(458.4)
Financing Activities
Net Cash Flows from (Used for) Financing Activities	177.6	331.3
Net Increase (Decrease) in Cash and Cash Equivalents	0	0
Cash and Cash Equivalents at Beginning of Period	0	0
Cash and Cash Equivalents at End of Period	0	0		0
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid	261.1	213.8
Organization and Summary of Significant Accounting Policies (Textuals)
NET INCOME (LOSS)	104.3	84.1	[1]
Retained Earnings						1,193.5	1,089.2
AEP Texas Inc. [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents	3.1					0.1	3.1
Restricted Cash						100.6	156.7
Total Cash, Cash Equivalents and Restricted Cash						100.7	159.8
Total Cash, Cash Equivalents and Restricted Cash						100.7	159.8	107.2	157.2
Revenues
TOTAL REVENUES	390.7	371.6
Expenses
Depreciation and Amortization	138.9	110
TOTAL EXPENSES	319.9	289.8
OPERATING INCOME (LOSS)	70.8	81.8
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction	1.8	5.5
Interest Expense	(37.4)	(35)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	38.4	55.9
Income Tax Expense (Benefit)	4	9.1
NET INCOME (LOSS)	34.4	46.8
Operating Activities
NET INCOME (LOSS)	34.4	46.8
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization	138.9	110
Deferred Income Taxes	(11)	(4.4)
Allowance for Equity Funds Used During Construction	(1.8)	(5.5)
Change in Other Noncurrent Assets	(3.2)	(12.7)
Change in Other Noncurrent Liabilities	(5.7)	6.5
Accounts Receivable, Net	(7.8)	1.8
Accounts Payable	4.2	(25.9)
Accrued Taxes, Net	57.5	25.2
Net Cash Flows from (Used for) Operating Activities	126.8	79
Investing Activities
Net Cash Flows from (Used for) Investing Activities	(336.6)	(364.4)
Financing Activities
Net Cash Flows from (Used for) Financing Activities	150.7	235.4
Cash and Cash Equivalents at Beginning of Period	3.1
Cash and Cash Equivalents at End of Period	0.1
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid	195.7	169.3
Organization and Summary of Significant Accounting Policies (Textuals)
NET INCOME (LOSS)	34.4	46.8
Retained Earnings						1,372.1	1,337.7
Appalachian Power Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents	2.9					2.9	4.2
Restricted Cash						18.3	25.6
Total Cash, Cash Equivalents and Restricted Cash						21.2	29.8	11.3	19.2
Revenues
TOTAL REVENUES	792.8	820.4
Expenses
Depreciation and Amortization	112.5	108.5
TOTAL EXPENSES	640.7	627.4
OPERATING INCOME (LOSS)	152.1	193
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction	1.7	2.6
Interest Expense	(49.3)	(47.4)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	109.6	153.5
Income Tax Expense (Benefit)	(24.1)	28
NET INCOME (LOSS)	133.7	125.5
Operating Activities
NET INCOME (LOSS)	133.7	125.5
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization	112.5	108.5
Deferred Income Taxes	(45)	11
Allowance for Equity Funds Used During Construction	(1.7)	(2.6)
Change in Other Noncurrent Assets	(12.1)	3.9
Change in Other Noncurrent Liabilities	(20.5)	37.9
Accounts Receivable, Net	19.5	(14.2)
Accounts Payable	(8.3)	(21.6)
Accrued Taxes, Net	13.7	17.8
Net Cash Flows from (Used for) Operating Activities	250.5	199.5
Investing Activities
Net Cash Flows from (Used for) Investing Activities	(383.5)	(214.1)
Financing Activities
Net Cash Flows from (Used for) Financing Activities	124.4	6.7
Cash and Cash Equivalents at Beginning of Period	4.2
Cash and Cash Equivalents at End of Period	2.9
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid	87.8	94.5
Organization and Summary of Significant Accounting Policies (Textuals)
NET INCOME (LOSS)	133.7	125.5
Retained Earnings						2,005.7	1,922
Ohio Power Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents	3.3					3.3	4.9
Restricted Cash						16.5	27.6
Total Cash, Cash Equivalents and Restricted Cash						19.8	32.5	17.3	29.7
Revenues
TOTAL REVENUES	836.8	790.9
Expenses
Depreciation and Amortization	63.3	64.8
TOTAL EXPENSES	674.3	673.6
OPERATING INCOME (LOSS)	162.5	117.3
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction	5.2	2.5
Interest Expense	(24.6)	(25.2)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS	147.8	100.1
Income Tax Expense (Benefit)	19.8	20.5
NET INCOME (LOSS)	128	79.6
Operating Activities
NET INCOME (LOSS)	128	79.6
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization	63.3	64.8
Deferred Income Taxes	10.1	(4.9)
Allowance for Equity Funds Used During Construction	(5.2)	(2.5)
Change in Other Noncurrent Assets	(7.3)	14.3
Change in Other Noncurrent Liabilities	17.6	40.6
Accounts Receivable, Net	31.7	38.8
Accounts Payable	(23.9)	(22.5)
Accrued Taxes, Net	(114.4)	(92.8)
Net Cash Flows from (Used for) Operating Activities	117.2	184.8
Investing Activities
Net Cash Flows from (Used for) Investing Activities	(194.8)	(366.9)
Financing Activities
Net Cash Flows from (Used for) Financing Activities	64.9	169.7
Cash and Cash Equivalents at Beginning of Period	4.9
Cash and Cash Equivalents at End of Period	3.3
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid	72.8	52.3
Organization and Summary of Significant Accounting Policies (Textuals)
NET INCOME (LOSS)	$ 128	79.6
Retained Earnings						$ 1,239.4	$ 1,136.4
Previously Reported [Member] | AEP Transmission Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		0		0				0	0
Revenues
TOTAL REVENUES		193.5
Expenses
Depreciation and Amortization		30.6
TOTAL EXPENSES		80.9
OPERATING INCOME (LOSS)		112.6
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction		15.3
Interest Expense		(19.9)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS		108.4
Income Tax Expense (Benefit)		22.5
NET INCOME (LOSS)		85.9
Operating Activities
NET INCOME (LOSS)		85.9
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization		30.6
Deferred Income Taxes		15.7
Allowance for Equity Funds Used During Construction		(15.3)
Change in Other Noncurrent Assets		2.7
Accounts Receivable, Net		(10.1)
Accounts Payable		(12.3)
Accrued Taxes, Net		(33.6)
Net Cash Flows from (Used for) Operating Activities		127.1
Investing Activities
Net Cash Flows from (Used for) Investing Activities		(458.4)
Financing Activities
Net Cash Flows from (Used for) Financing Activities		331.3
Net Increase (Decrease) in Cash and Cash Equivalents		0
Cash and Cash Equivalents at Beginning of Period		0
Cash and Cash Equivalents at End of Period		0		0
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid		210.6
Organization and Summary of Significant Accounting Policies (Textuals)
NET INCOME (LOSS)		85.9
Revision [Member] | AEP Transmission Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		0		0				$ 0	0
Revenues
TOTAL REVENUES		(1.8)
Expenses
Depreciation and Amortization		(0.3)
TOTAL EXPENSES		(0.3)
OPERATING INCOME (LOSS)		(1.5)
Nonoperating Income (Expense)
Allowance for Equity Funds Used During Construction		(0.4)
Interest Expense		(0.4)
INCOME BEFORE INCOME TAX EXPENSE AND EQUITY EARNINGS		(2.3)
Income Tax Expense (Benefit)		(0.5)
NET INCOME (LOSS)		(1.8)
Operating Activities
NET INCOME (LOSS)		(1.8)
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities
Utilities Operating Expense, Depreciation and Amortization		(0.3)
Deferred Income Taxes		(0.2)
Allowance for Equity Funds Used During Construction		0.4
Change in Other Noncurrent Assets		0.2
Accounts Receivable, Net		0.5
Accounts Payable		1.6
Accrued Taxes, Net		(0.4)
Net Cash Flows from (Used for) Operating Activities		0
Investing Activities
Net Cash Flows from (Used for) Investing Activities		0
Financing Activities
Net Cash Flows from (Used for) Financing Activities		0
Net Increase (Decrease) in Cash and Cash Equivalents		0
Cash and Cash Equivalents at Beginning of Period		0
Cash and Cash Equivalents at End of Period		0		$ 0
Supplementary Information
Construction in Progress Expenditures Incurred but Not yet Paid		3.2
Organization and Summary of Significant Accounting Policies (Textuals)
Error Corrections and Prior Period Adjustments, Description				AEPTCo recorded a pretax out of period correction of an error of approximately $17 million related to revenue recorded from 2013 through March 31, 2018 in the second quarter of 2018	The impact of this misstatement reduced AEPTCo’s pretax income by approximately $7 million on a cumulative basis for the period 2011 through June 30, 2018
NET INCOME (LOSS)		$ (1.8)
Retained Earnings									$ (15)
[1]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[2]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.

Comprehensive Income (Details)

Comprehensive Income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		$ (120.4)	$ (67.8)
Change in Fair Value Recognized in AOCI		(38.8)	12.8
Interest Rate
Interest Expense		255.8	234
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		10.7	(14.6)
Income Tax (Expense) Benefit		(44.5)	(102)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		8.5	(11.5)
Net Current Period Other Comprehensive Income (Loss)		(30.3)	1.3
ASU 2018-02 Adoption			(3)
ASU 2016-01 Adoption			0
Ending Balance in AOCI		(150.7)	(95.4)
Securities Available for Sale [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI			11.9
Change in Fair Value Recognized in AOCI			0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit			0
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit			0
Net Current Period Other Comprehensive Income (Loss)			0
ASU 2018-02 Adoption			0
ASU 2016-01 Adoption			(11.9)
Ending Balance in AOCI			0
Pension and OPEB [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(84.8)	(38.3)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(1.8)	(1.8)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(1.4)	(1.4)
Net Current Period Other Comprehensive Income (Loss)		(1.4)	(1.4)
ASU 2018-02 Adoption			(8.2)
ASU 2016-01 Adoption			0
Ending Balance in AOCI		(86.2)	(47.9)
Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		(30.3)	1.3
ASU 2018-02 Adoption			(17)
ASU 2016-01 Adoption			(11.9)
Commodity [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(23)	(28.4)
Change in Fair Value Recognized in AOCI		(38.8)	12.8
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		12.3	(13.1)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		9.7	(10.3)
Net Current Period Other Comprehensive Income (Loss)		(29.1)	2.5
ASU 2018-02 Adoption			(6.1)
ASU 2016-01 Adoption			0
Ending Balance in AOCI		(52.1)	(32)
Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(12.6)	(13)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.2	0.3
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.2	0.2
Net Current Period Other Comprehensive Income (Loss)		0.2	0.2
ASU 2018-02 Adoption			(2.7)
ASU 2016-01 Adoption			0
Ending Balance in AOCI		(12.4)	(15.5)
Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale		861.8	990.3
Reclassifications from Accumulated Other Comprehensive Income [Member]
Interest Rate
Interest Expense	[1]	0.2	0.3
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(4.8)	(5)
Amortization of Actuarial (Gains) Losses		3	3.2
Income Tax (Expense) Benefit		2.2	(3.1)
Reclassifications from Accumulated Other Comprehensive Income [Member] | Securities Available for Sale [Member]
Interest Rate
Interest Expense	[1]		0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)			0
Amortization of Actuarial (Gains) Losses			0
Income Tax (Expense) Benefit			0
Reclassifications from Accumulated Other Comprehensive Income [Member] | Pension and OPEB [Member]
Interest Rate
Interest Expense	[1]	0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(4.8)	(5)
Amortization of Actuarial (Gains) Losses		3	3.2
Income Tax (Expense) Benefit		(0.4)	(0.4)
Reclassifications from Accumulated Other Comprehensive Income [Member] | Commodity [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		0	0
Amortization of Actuarial (Gains) Losses		0	0
Income Tax (Expense) Benefit		2.6	(2.8)
Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	0.2	0.3
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		0	0
Amortization of Actuarial (Gains) Losses		0	0
Income Tax (Expense) Benefit		0	0.1
Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale	[1]	12.3	(13.1)
Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Securities Available for Sale [Member]
Commodity
Purchased Electricity for Resale	[1]		0
Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Pension and OPEB [Member]
Commodity
Purchased Electricity for Resale	[1]	0	0
Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Commodity [Member] | Cash Flow Hedges [Member]
Commodity
Purchased Electricity for Resale	[1]	12.3	(13.1)
Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Commodity
Purchased Electricity for Resale	[1]	0	0
AEP Texas Inc. [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(15.1)	(12.6)
Change in Fair Value Recognized in AOCI		0	0
Interest Rate
Interest Expense		37.4	35
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.4	0.4
Income Tax (Expense) Benefit		(4)	(9.1)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.3	0.3
Net Current Period Other Comprehensive Income (Loss)		0.3	0.3
ASU 2018-02 Adoption			(0.9)
Ending Balance in AOCI		(14.8)	(15)
AEP Texas Inc. [Member] | Pension and OPEB [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(10.7)	(8.1)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0	0.1
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0	0.1
Net Current Period Other Comprehensive Income (Loss)		0	0.1
ASU 2018-02 Adoption			(1.8)
Ending Balance in AOCI		(10.7)	(9.8)
AEP Texas Inc. [Member] | Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		0.3	0.3
ASU 2018-02 Adoption			(2.7)
AEP Texas Inc. [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(4.4)	(4.5)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.4	0.3
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.3	0.2
Net Current Period Other Comprehensive Income (Loss)		0.3	0.2
ASU 2018-02 Adoption			(0.9)
Ending Balance in AOCI		(4.1)	(5.2)
AEP Texas Inc. [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member]
Interest Rate
Interest Expense	[1]	0.4	0.3
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Actuarial (Gains) Losses			0.1
Income Tax (Expense) Benefit		0.1	0.1
AEP Texas Inc. [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Pension and OPEB [Member]
Interest Rate
Interest Expense	[1]	0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Actuarial (Gains) Losses			0.1
Income Tax (Expense) Benefit		0	0
AEP Texas Inc. [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	0.4	0.3
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Actuarial (Gains) Losses			0
Income Tax (Expense) Benefit		0.1	0.1
Appalachian Power Co [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(5)	1.3
Change in Fair Value Recognized in AOCI		0	(0.7)
Interest Rate
Interest Expense		49.3	47.4
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(1.1)	(0.4)
Income Tax (Expense) Benefit		24.1	(28)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(0.8)	(0.3)
Net Current Period Other Comprehensive Income (Loss)		(0.8)	(1)
ASU 2018-02 Adoption			0.4
Ending Balance in AOCI		(5.8)	0.6
Appalachian Power Co [Member] | Pension and OPEB [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(6.8)	(0.9)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(0.8)	(1)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(0.6)	(0.8)
Net Current Period Other Comprehensive Income (Loss)		(0.6)	(0.8)
ASU 2018-02 Adoption			(0.2)
Ending Balance in AOCI		(7.4)	(1.9)
Appalachian Power Co [Member] | Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		(0.8)	(1)
ASU 2018-02 Adoption			0.3
Appalachian Power Co [Member] | Commodity [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI			0
Change in Fair Value Recognized in AOCI			(0.7)
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit			0.9
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit			0.7
Net Current Period Other Comprehensive Income (Loss)			0
ASU 2018-02 Adoption			0
Ending Balance in AOCI			0
Appalachian Power Co [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		1.8	2.2
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(0.3)	(0.3)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(0.2)	(0.2)
Net Current Period Other Comprehensive Income (Loss)		(0.2)	(0.2)
ASU 2018-02 Adoption			0.5
Ending Balance in AOCI		1.6	2.5
Appalachian Power Co [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale		110.6	205.9
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member]
Interest Rate
Interest Expense	[1]	(0.3)	(0.3)
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(1.3)	(1.3)
Amortization of Actuarial (Gains) Losses		0.5	0.3
Income Tax (Expense) Benefit		(0.3)	(0.1)
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Pension and OPEB [Member]
Interest Rate
Interest Expense	[1]	0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(1.3)	(1.3)
Amortization of Actuarial (Gains) Losses		0.5	0.3
Income Tax (Expense) Benefit		(0.2)	(0.2)
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Commodity [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]		0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)			0
Amortization of Actuarial (Gains) Losses			0
Income Tax (Expense) Benefit			0.2
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	(0.3)	(0.3)
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		0	0
Amortization of Actuarial (Gains) Losses		0	0
Income Tax (Expense) Benefit		(0.1)	(0.1)
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale	[1]		0.9
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Pension and OPEB [Member]
Commodity
Purchased Electricity for Resale	[1]		0
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Commodity [Member] | Cash Flow Hedges [Member]
Commodity
Purchased Electricity for Resale	[1]		0.9
Appalachian Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Purchased Electricity for Resale [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Commodity
Purchased Electricity for Resale	[1]		0
Indiana Michigan Power Co [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(13.8)	(12.1)
Change in Fair Value Recognized in AOCI		0	0
Interest Rate
Interest Expense		28.9	29.7
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.5	0.5
Income Tax (Expense) Benefit		2.7	(12.4)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.4	0.4
Net Current Period Other Comprehensive Income (Loss)		0.4	0.4
ASU 2018-02 Adoption			(2.4)
Ending Balance in AOCI		(13.4)	(14.4)
Indiana Michigan Power Co [Member] | Pension and OPEB [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(2.3)	(1.4)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0	0
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0	0
Net Current Period Other Comprehensive Income (Loss)		0	0
ASU 2018-02 Adoption			(0.3)
Ending Balance in AOCI		(2.3)	(1.7)
Indiana Michigan Power Co [Member] | Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		0.4	0.4
ASU 2018-02 Adoption			(2.7)
Indiana Michigan Power Co [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(11.5)	(10.7)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.5	0.5
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.4	0.4
Net Current Period Other Comprehensive Income (Loss)		0.4	0.4
ASU 2018-02 Adoption			(2.4)
Ending Balance in AOCI		(11.1)	(12.7)
Indiana Michigan Power Co [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale		69.6	55.6
Indiana Michigan Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member]
Interest Rate
Interest Expense	[1]	0.5	0.5
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(0.2)	(0.2)
Amortization of Actuarial (Gains) Losses		0.2	0.2
Income Tax (Expense) Benefit		0.1	0.1
Indiana Michigan Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Pension and OPEB [Member]
Interest Rate
Interest Expense	[1]	0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(0.2)	(0.2)
Amortization of Actuarial (Gains) Losses		0.2	0.2
Income Tax (Expense) Benefit		0	0
Indiana Michigan Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	0.5	0.5
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		0	0
Amortization of Actuarial (Gains) Losses		0	0
Income Tax (Expense) Benefit		0.1	0.1
Ohio Power Co [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		1
Interest Rate
Interest Expense		24.6	25.2
Amortization Of Pension And Other Postretirement Benefit Plans
Income Tax (Expense) Benefit		(19.8)	(20.5)
Net Current Period Other Comprehensive Income (Loss)		(0.3)	(0.3)
ASU 2018-02 Adoption			0.4
Ending Balance in AOCI		0.7
Ohio Power Co [Member] | Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		(0.3)	(0.3)
ASU 2018-02 Adoption			0.4
Ohio Power Co [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		1	1.9
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(0.4)	(0.4)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(0.3)	(0.3)
Net Current Period Other Comprehensive Income (Loss)		(0.3)	(0.3)
ASU 2018-02 Adoption			0.4
Ending Balance in AOCI		0.7	2
Ohio Power Co [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale		174.2	205.5
Ohio Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	(0.4)	(0.4)
Amortization Of Pension And Other Postretirement Benefit Plans
Income Tax (Expense) Benefit		(0.1)	(0.1)
Public Service Co Of Oklahoma [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		2.1
Interest Rate
Interest Expense		16.9	14.7
Amortization Of Pension And Other Postretirement Benefit Plans
Income Tax (Expense) Benefit		0	1.4
Net Current Period Other Comprehensive Income (Loss)		(0.2)	(0.2)
ASU 2018-02 Adoption			0.5
Ending Balance in AOCI		1.9
Public Service Co Of Oklahoma [Member] | Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		(0.2)	(0.2)
ASU 2018-02 Adoption			0.5
Public Service Co Of Oklahoma [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		2.1	2.6
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(0.3)	(0.3)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(0.2)	(0.2)
Net Current Period Other Comprehensive Income (Loss)		(0.2)	(0.2)
ASU 2018-02 Adoption			0.5
Ending Balance in AOCI		1.9	2.9
Public Service Co Of Oklahoma [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale		122.9	122.4
Public Service Co Of Oklahoma [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	(0.3)	(0.3)
Amortization Of Pension And Other Postretirement Benefit Plans
Income Tax (Expense) Benefit		(0.1)	(0.1)
Southwestern Electric Power Co [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(5.4)	(4)
Change in Fair Value Recognized in AOCI		0	0
Interest Rate
Interest Expense		29.7	32.2
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.1	0.1
Income Tax (Expense) Benefit		(0.7)	(2.9)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.1	0.1
Net Current Period Other Comprehensive Income (Loss)		0.1	0.1
ASU 2018-02 Adoption			(1.3)
Ending Balance in AOCI		(5.3)	(4.8)
Southwestern Electric Power Co [Member] | Pension and OPEB [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(2.1)	2
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		(0.4)	(0.4)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		(0.3)	(0.3)
Net Current Period Other Comprehensive Income (Loss)		(0.3)	(0.3)
ASU 2018-02 Adoption			0.4
Ending Balance in AOCI		(2.4)	2.1
Southwestern Electric Power Co [Member] | Accumulated Other Comprehensive Income [Member]
Amortization Of Pension And Other Postretirement Benefit Plans
Net Current Period Other Comprehensive Income (Loss)		0.1	0.1
ASU 2018-02 Adoption			(0.9)
Southwestern Electric Power Co [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Beginning Balance in AOCI		(3.3)	(6)
Change in Fair Value Recognized in AOCI		0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Reclassifications from AOCI, before Income Tax (Expense) Benefit		0.5	0.5
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit		0.4	0.4
Net Current Period Other Comprehensive Income (Loss)		0.4	0.4
ASU 2018-02 Adoption			(1.3)
Ending Balance in AOCI		(2.9)	(6.9)
Southwestern Electric Power Co [Member] | Purchased Electricity for Resale [Member]
Commodity
Purchased Electricity for Resale		32.6	42.7
Southwestern Electric Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member]
Interest Rate
Interest Expense	[1]	0.5	0.5
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(0.5)	(0.5)
Amortization of Actuarial (Gains) Losses		0.1	0.1
Income Tax (Expense) Benefit		0	0
Southwestern Electric Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Pension and OPEB [Member]
Interest Rate
Interest Expense	[1]	0	0
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		(0.5)	(0.5)
Amortization of Actuarial (Gains) Losses		0.1	0.1
Income Tax (Expense) Benefit		(0.1)	(0.1)
Southwestern Electric Power Co [Member] | Reclassifications from Accumulated Other Comprehensive Income [Member] | Interest Rate [Member] | Cash Flow Hedges [Member]
Interest Rate
Interest Expense	[1]	0.5	0.5
Amortization Of Pension And Other Postretirement Benefit Plans
Amortization of Prior Service Cost (Credit)		0	0
Amortization of Actuarial (Gains) Losses		0	0
Income Tax (Expense) Benefit		$ 0.1	$ 0.1
[1]	Amounts reclassified to the referenced line item on the statements of income.

Rate Matters Regulated Operatio

Rate Matters Regulated Operations (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Dec. 31, 2018
Public Utilities, General Disclosures [Line Items]
Gross Investment		$ 21,780.6	$ 21,699.9
Accumulated Depreciation and Amortization		18,182.6	17,986.1
Total Property, Plant and Equipment - Net		55,968.6	55,099.1
Materials and Supplies		586.3	579.6
Regulatory Liability, Noncurrent		8,669.8	8,540.3
Regulatory Assets, Noncurrent		3,297.9	3,310.4
Oklaunion Generating Station [Member] | Generating Units Probable of Abandonment [Member]
Public Utilities, General Disclosures [Line Items]
Gross Investment		106.5
Accumulated Depreciation and Amortization		68.7
Total Property, Plant and Equipment - Net		37.8
Oklaunion Power Station Accelerated Depreciation		10.9
Materials and Supplies		3.1
Regulatory Liability, Noncurrent		$ 5
Expected Retirement Date		2020
Remaining Recovery Period, Plant Depreciation		27 years
AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Gross Investment		$ 352	352.1
Accumulated Depreciation and Amortization		1,686.6	1,651.2
Total Property, Plant and Equipment - Net		8,220	7,991.8
Materials and Supplies		54.1	52.8
Regulatory Liability, Noncurrent		1,344.1	1,344.3
Regulatory Assets, Noncurrent		426.7	430
AEP Transmission Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization		306.7	271.9
Total Property, Plant and Equipment - Net		8,260.5	7,996.2
Materials and Supplies		19.6	19
Regulatory Liability, Noncurrent		527.9	521.3
Regulatory Assets, Noncurrent		10.5	12.9
Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Gross Investment		6,531.5	6,509.6
Accumulated Depreciation and Amortization		4,174.9	4,124.4
Total Property, Plant and Equipment - Net		10,730.7	10,668.3
Materials and Supplies		102.1	100.1
Regulatory Liability, Noncurrent		1,415.7	1,449.7
Regulatory Assets, Noncurrent		469.6	475.8
Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Gross Investment		4,895	4,887.2
Accumulated Depreciation and Amortization		3,208.4	3,151.6
Total Property, Plant and Equipment - Net		6,680.6	6,611.2
Materials and Supplies		166.1	167.3
Regulatory Liability, Noncurrent		1,743.5	1,574.5
Regulatory Assets, Noncurrent		504.7	512.5
Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization		2,224.1	2,218.6
Total Property, Plant and Equipment - Net		6,395.2	6,274.9
Materials and Supplies		42.9	42.9
Regulatory Liability, Noncurrent		1,234.4	1,221.2
Regulatory Assets, Noncurrent		375	387.5
Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Gross Investment		1,568.6	1,577
Accumulated Depreciation and Amortization		1,496.2	1,472.9
Total Property, Plant and Equipment - Net		3,976.9	3,966.7
Materials and Supplies		43.9	44.8
Regulatory Liability, Noncurrent		861.2	864.7
Regulatory Assets, Noncurrent		$ 365.1	369
Public Service Co Of Oklahoma [Member] | Oklaunion Generating Station [Member] | Generating Units Probable of Abandonment [Member]
Public Utilities, General Disclosures [Line Items]
Expected Retirement Date		2020
Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Gross Investment		$ 4,711.6	4,672.6
Accumulated Depreciation and Amortization		2,760.6	2,808.3
Total Property, Plant and Equipment - Net		6,915.4	6,871.8
Materials and Supplies		69.1	67.5
Regulatory Liability, Noncurrent		922.7	923
Regulatory Assets, Noncurrent		226.6	230.8
Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[1]	287.8	288
Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		152.4	152.6
Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[1]	40.4	44.9
Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		3.4	3.3
Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.1	1
Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		10.9	5.5
Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		61	64.4
Asset Retirement Obligation - Arkansas, Louisiana [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		5.8	5.3
Kentucky Deferred Purchase Power Expenses [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		18.4	14.5
Oklaunion Power Station Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[2]	10.9	5.5
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		16.4	14.8
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.3	0.3
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		15.4	20.7
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0	0.6
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		3.4	3.3
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.1	1
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		3.7	3.6
Plant Retirement Costs - Asset Retirement Obligation Costs | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		35.3	35.3
Plant Retirement Costs - Asset Retirement Obligation Costs | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		35.3	35.3
Plant Retirement Costs - Materials and Supplies [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		5.1	9
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization		91
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization		91
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		50.3	50.3
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		50.3	50.3
Rate Case Expense - Texas [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.9	4.9
Rate Case Expense [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.4	0.2
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[2]	152	152.4
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[2]	152	$ 152.4
Storm Costs Hurricane Harvey [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[2]	137
Storm Costs Hurricane Harvey [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[2]	$ 137
[1]	In 2015, APCo recorded a $91 million
[2]	As of March 31, 2019 , AEP Texas has deferred $137 million

Rate Matters East Companies (De

Rate Matters East Companies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization	$ 18,182.6	$ 17,986.1
Construction Work in Progress	4,910.9	4,393.9
AEP Transmission Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization	306.7	271.9
Construction Work in Progress	1,812.2	1,578.3
Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization	4,174.9	4,124.4
Construction Work in Progress	524.9	490.2
Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization	3,208.4	3,151.6
Construction Work in Progress	533.5	465.3
Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Accumulated Depreciation and Amortization	2,224.1	2,218.6
Construction Work in Progress	$ 461	$ 432.1
Virginia Legislation Affecting Earnings Reviews [Member]
Public Utilities, General Disclosures [Line Items]
Percent of Excess Earnings Subject to Refund	70.00%
Basis Points Over Authorized Return on Equity Considered Excess Earnings	70.00%
Approved Return on Common Equity	9.42%
Virginia Legislation Affecting Earnings Reviews [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Percent of Excess Earnings Subject to Refund	70.00%
Basis Points Over Authorized Return on Equity Considered Excess Earnings	70.00%
Approved Return on Common Equity	9.42%
Virginia Staff Depreciation Study Request [Member]
Public Utilities, General Disclosures [Line Items]
Potential Increase to Total Annual Depreciation Rates	$ 21
Potential Increase to Annual Transmission Depreciation Rates	6
Virginia Staff Depreciation Study Request [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Potential Increase to Total Annual Depreciation Rates	21
Potential Increase to Annual Transmission Depreciation Rates	6
Virginia Tax Reform [Member]
Public Utilities, General Disclosures [Line Items]
Refund Due to Tax Reform	40
Refund for Excess ADIT Associated with Certain Depreciable Property	9
Refund for Excess ADIT Not Subject to Rate Normalization Requirements	94
One Time Refund of Estimated Excess Taxes Collected	22
Virginia Tax Reform [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Refund Due to Tax Reform	40
Refund for Excess ADIT Associated with Certain Depreciable Property	9
Refund for Excess ADIT Not Subject to Rate Normalization Requirements	94
One Time Refund of Estimated Excess Taxes Collected	$ 22
2018 West Virginia Base Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity	9.75%
Refund for Excess ADIT Not Subject to Rate Normalization Requirements	$ 24
Amount of Increase Related to Annual Depreciation Rates	32
Requested Annual Increase	$ 115
Requested Return on Equity	10.22%
Approved Amount of Increase Related to Annual Depreciation Rates	$ 18
Regulatory Assets Used to Offset Tax Savings and Excess ADIT Due to Tax Reform	14
Adjusted Annual Increase Request due to Tax Reform	95
Approved Annual Revenue Increase	$ 44
2018 West Virginia Base Rate Case [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity	9.75%
Refund for Excess ADIT Not Subject to Rate Normalization Requirements	$ 19
Amount of Increase Related to Annual Depreciation Rates	28
Requested Annual Increase	$ 98
Requested Return on Equity	10.22%
Approved Amount of Increase Related to Annual Depreciation Rates	$ 14
Regulatory Assets Used to Offset Tax Savings and Excess ADIT Due to Tax Reform	12
Adjusted Annual Increase Request due to Tax Reform	80
Approved Annual Revenue Increase	36
Michigan Tax Reform [Member]
Public Utilities, General Disclosures [Line Items]
Refund for Excess ADIT Associated with Certain Depreciable Property	68
Refund for Excess ADIT Not Subject to Rate Normalization Requirements	37
Michigan Tax Reform [Member] | Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Refund for Excess ADIT Associated with Certain Depreciable Property	68
Refund for Excess ADIT Not Subject to Rate Normalization Requirements	$ 37
Ohio Electric Security Plan Filing [Member]
Public Utilities, General Disclosures [Line Items]
Return on Common Equity Filed in the Pending Stipulation Agreement	10.00%
Staff Calculated Overspending	$ 10
Ohio Electric Security Plan Filing [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Return on Common Equity Filed in the Pending Stipulation Agreement	10.00%
Staff Calculated Overspending	$ 10
2016 SEET Filing [Member]
Public Utilities, General Disclosures [Line Items]
Provision for Refund	58
2016 SEET Filing [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Provision for Refund	$ 58
FERC Transmission Complaint [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity	10.99%
Intervenor Recommended Return on Common Equity	8.32%
Return On Common Equity Per Settlement Agreement	9.85%
Return on Common Equity Inclusive of RTO Per Settlement Agreement	10.35%
RTO Incentive Adder Per Settlement Agreement	0.50%
One Time Refund to Customers Per Settlement Agreement	$ 50
Increased Cap on Equity Portion of the Capital Structure Per Settlement Agreement	55.00%
Original Cap on Equity Portion of the Capital Structure Prior to Settlement Agreement	50.00%
Minimum [Member] | Ohio Electric Security Plan Filing [Member]
Public Utilities, General Disclosures [Line Items]
Rate Caps Related to the Distribution Investment Rider Range	$ 215
Minimum [Member] | Ohio Electric Security Plan Filing [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Rate Caps Related to the Distribution Investment Rider Range	215
Maximum [Member] | Ohio Electric Security Plan Filing [Member]
Public Utilities, General Disclosures [Line Items]
Rate Caps Related to the Distribution Investment Rider Range	290
Maximum [Member] | Ohio Electric Security Plan Filing [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Rate Caps Related to the Distribution Investment Rider Range	$ 290

Rate Matters West Companies (De

Rate Matters West Companies (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Dec. 31, 2018
Public Utilities, General Disclosures [Line Items]
Construction Work in Progress		$ 4,910.9	$ 4,393.9
AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Construction Work in Progress		941.8	836.2
Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Construction Work in Progress		98.6	94
Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Construction Work in Progress		193.4	$ 199.3
AEP Texas Interim Transmission and Distribution Rates [Member]
Public Utilities, General Disclosures [Line Items]
AEP Texas Cumulative Revenues Subject to Review		1,100
AEP Texas Interim Transmission and Distribution Rates [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
AEP Texas Cumulative Revenues Subject to Review		1,100
Texas Storm Cost Securitization [Member]
Public Utilities, General Disclosures [Line Items]
Annual Recovery of Storm Costs through Base Rates		1
AEP Texas Total Storm-Related Costs		152
AEP Texas Hurricane Harvey Storm-Related Costs		137
Distribution-Related System Restoration Costs		264.6
Estimated Carrying Costs		26.9
Up-front Qualified Costs		4.6
Total Distribution-Related System Restoration Costs		296.1
Insurance Proceeds and Government Grants		(3.1)
Excess ADIT	[1]	(63.5)
Securitization Request for Distribution Related Assets		229.5
Transmission Related Assets to be Recovered at a Later Time		95
Texas Storm Cost Securitization [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Annual Recovery of Storm Costs through Base Rates		1
AEP Texas Total Storm-Related Costs		152
AEP Texas Hurricane Harvey Storm-Related Costs		137
Distribution-Related System Restoration Costs		264.6
Estimated Carrying Costs		26.9
Up-front Qualified Costs		4.6
Total Distribution-Related System Restoration Costs		296.1
Insurance Proceeds and Government Grants		(3.1)
Excess ADIT	[1]	(63.5)
Securitization Request for Distribution Related Assets		229.5
Transmission Related Assets to be Recovered at a Later Time		$ 95
ETT Interim Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Parent Ownership Interest In ETT		50.00%
AEP Share Of ETT Cumulative Revenues Subject To Review		$ 918
2018 Oklahoma Base Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		$ 88
Requested Return on Equity		10.30%
Amount Of Increased Depreciation Expense Requested		$ 13
Amount of Increase Related to Increased Storm Expense Amortization		7
Approved Annual Revenue Increase		$ 46
Approved Return on Common Equity		9.40%
Revenue Cap on New Distribution Reliability and Safety Rider		$ 5
2018 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		$ 88
Requested Return on Equity		10.30%
Amount Of Increased Depreciation Expense Requested		$ 13
Amount of Increase Related to Increased Storm Expense Amortization		7
Approved Annual Revenue Increase		$ 46
Approved Return on Common Equity		9.40%
Revenue Cap on New Distribution Reliability and Safety Rider		$ 5
2012 Texas Base Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
2013 Reversal of Previously Recorded Regulatory Disallowances		114
Resulting Approved Base Rate Increase		52
2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
2013 Reversal of Previously Recorded Regulatory Disallowances		114
Resulting Approved Base Rate Increase		52
2012 Texas Base Rate Case [Member] | Turk Generating Plant [Member]
Public Utilities, General Disclosures [Line Items]
Property, Plant and Equipment, Net		$ 1,500
Texas Jurisdictional Share of Turk Plant		33.00%
2012 Texas Base Rate Case [Member] | Turk Generating Plant [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Property, Plant and Equipment, Net		$ 1,500
Texas Jurisdictional Share of Turk Plant		33.00%
2016 Texas Base Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity		10.00%
Approved Return on Common Equity		9.60%
Requested Net Increase in Texas Annual Revenues		$ 69
Approved Net Increase in Texas Annual Revenues		50
Approved Additional Vegetation Management Expenses		2
Impairment Charge Total		19
Impairment Charge Welsh Plant, Unit 2		7
Impairment Charge Disallowed Plant Investments		12
Additional Revenues Recognized to be Surcharged to Customers		32
Additional Recognized Expenses Consisting Primarily of Depreciation and Vegetation Management		$ 7
2016 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity		10.00%
Approved Return on Common Equity		9.60%
Requested Net Increase in Texas Annual Revenues		$ 69
Approved Net Increase in Texas Annual Revenues		50
Approved Additional Vegetation Management Expenses		2
Impairment Charge Total		19
Impairment Charge Welsh Plant, Unit 2		7
Impairment Charge Disallowed Plant Investments		12
Additional Revenues Recognized to be Surcharged to Customers		32
Additional Recognized Expenses Consisting Primarily of Depreciation and Vegetation Management		7
Louisiana 2018 Formula Rate Filing [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		28
Adjusted Requested Annual Increase		18
Refund for Current Year Tax Reform Rate Change		11
Louisiana 2018 Formula Rate Filing [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		28
Adjusted Requested Annual Increase		18
Refund for Current Year Tax Reform Rate Change		11
Welsh Plant, Units 1 and 3 - Environmental Projects [Member] | Welsh Plant, Units 1 and 3 [Member]
Public Utilities, General Disclosures [Line Items]
Property, Plant and Equipment, Net		623
Projected Capital Costs		550
Construction Work in Progress		399
Total Amount of Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs		79
Total Amount Of Recovery Requested Related To Louisiana Retail Jurisdictional Share Of Environmental Costs		131
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferrals		10
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferred Unrecognized Equity		5
Welsh Plant, Units 1 and 3 - Environmental Projects [Member] | Welsh Plant, Units 1 and 3 [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Property, Plant and Equipment, Net		623
Projected Capital Costs		550
Construction Work in Progress		399
Total Amount of Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs		79
Total Amount Of Recovery Requested Related To Louisiana Retail Jurisdictional Share Of Environmental Costs		131
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferrals		10
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferred Unrecognized Equity		5
2019 Arkansas Base Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		$ 75
Requested Return on Equity		10.50%
Requested Annual Net Increase		$ 58
Requested Additional Vegetation Management Expenses		12
2019 Arkansas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		$ 75
Requested Return on Equity		10.50%
Requested Annual Net Increase		$ 58
Requested Additional Vegetation Management Expenses		$ 12
FERC Transmission Complaint - AEP SPP Participants [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity		10.70%
Intervenor Recommended Return On Common Equity Range		8.36%
Second Intervenor Recommended Return on Common Equity		8.71%
Return On Common Equity Per Settlement Agreement		10.00%
Return on Common Equity Inclusive of RTO Per Settlement Agreement		10.50%
RTO Incentive Adder Per Settlement Agreement		0.50%
[1]	(a)Amount represents Non-Hurricane Harvey Excess ADIT that is not subject to rate normalization requirements.

Commitments, Guarantees and C_3

Commitments, Guarantees and Contingencies (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)MW	Apr. 25, 2019USD ($)
Commitments, Guarantees and Contingencies (Textuals)
Utility Plant Generation Capacity | MW	2,278
Letters of Credit [Member]
Maximum Future Payments for Letters of Credit Under Uncommitted Facilities
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility	$ 105.8
Commitments, Guarantees and Contingencies (Textuals)
Letters of Credit Limit	1,200
Uncommitted Facility	305
Variable Rate PCBs Supported	45
Guarantees of Third Party Obligations [Member]
Commitments, Guarantees and Contingencies (Textuals)
Guarantees of Mine Reclamation, Amount	140
Mine Reclamation and Closing Liability, Noncurrent	107
Total Amount Collected through a Rider for Final Mine Closure and Reclamation Costs	76
Amount Collected through a Rider for Final Mine Closure - ARO Noncurrent	82
Amount Collected, Rider Mine Close Other Assets Noncurrent	6
Guarantees of Equity Method Investees [Member]
Commitments, Guarantees and Contingencies (Textuals)
Maximum Potential Amount of Future Payments Associated with Guarantee	75
AEP Texas Inc. [Member] | Letters of Credit [Member]
Maximum Future Payments for Letters of Credit Under Uncommitted Facilities
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility	$ 2.2
Indiana Michigan Power Co [Member]
Commitments, Guarantees and Contingencies (Textuals)
Utility Plant Generation Capacity | MW	2,278
Ohio Power Co [Member] | Letters of Credit [Member]
Maximum Future Payments for Letters of Credit Under Uncommitted Facilities
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility	$ 1.2
Southwestern Electric Power Co [Member] | Guarantees of Third Party Obligations [Member]
Commitments, Guarantees and Contingencies (Textuals)
Guarantees of Mine Reclamation, Amount	140
Mine Reclamation and Closing Liability, Noncurrent	107
Total Amount Collected through a Rider for Final Mine Closure and Reclamation Costs	76
Amount Collected through a Rider for Final Mine Closure - ARO Noncurrent	82
Amount Collected, Rider Mine Close Other Assets Noncurrent	6
June 2022 [Member] | Letters of Credit [Member]
Commitments, Guarantees and Contingencies (Textuals)
Revolving Credit Facilities	4,000
July 2019 [Member] | Letters of Credit [Member]
Commitments, Guarantees and Contingencies (Textuals)
Letters of Credit Outstanding, Amount	$ 46
Subsequent Event [Member] | Letters of Credit [Member]
Commitments, Guarantees and Contingencies (Textuals)
Uncommitted Facility		$ 50

Acquisitions and Impairments (D

Acquisitions and Impairments (Details) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 25, 2019USD ($)MW	Mar. 31, 2018USD ($)
Other Assets [Member] | Corporate and Other [Member]
Asset Impairment and Other Related Charges		$ 21
Sempra Renewables LLC [Member] | Subsequent Event [Member] | Generation And Marketing [Member]
Wind Generation (MWs) | MW	724
Noncash or Part Noncash Acquisition, Value of Assets Acquired	$ 1,100
Payments to Acquire Businesses, Gross	584
Noncash or Part Noncash Acquisition, Debt Assumed	358
Noncash or Part Noncash Acquisition, Other Assets Acquired	$ 110

Benefit Plans (Details)

Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension Plans [Member]
Components of Net Periodic Benefit Cost
Service Cost	$ 23.9	$ 24.4
Interest Cost	51.1	46.9
Expected Return on Plan Assets	(74)	(72.5)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	14.4	21.3
Net Periodic Benefit Cost (Credit)	15.4	20.1
Pension Plans [Member] | AEP Texas Inc. [Member]
Components of Net Periodic Benefit Cost
Service Cost	2.1	2.3
Interest Cost	4.4	4
Expected Return on Plan Assets	(6.4)	(6.4)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	1.2	1.8
Net Periodic Benefit Cost (Credit)	1.3	1.7
Pension Plans [Member] | Appalachian Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	2.4	2.3
Interest Cost	6.3	5.9
Expected Return on Plan Assets	(9.4)	(9.1)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	1.8	2.6
Net Periodic Benefit Cost (Credit)	1.1	1.7
Pension Plans [Member] | Indiana Michigan Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	3.4	3.4
Interest Cost	6	5.5
Expected Return on Plan Assets	(9.2)	(8.9)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	1.6	2.5
Net Periodic Benefit Cost (Credit)	1.8	2.5
Pension Plans [Member] | Ohio Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	2	2
Interest Cost	4.7	4.4
Expected Return on Plan Assets	(7.3)	(7.2)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	1.3	2
Net Periodic Benefit Cost (Credit)	0.7	1.2
Pension Plans [Member] | Public Service Co Of Oklahoma [Member]
Components of Net Periodic Benefit Cost
Service Cost	1.6	1.8
Interest Cost	2.6	2.4
Expected Return on Plan Assets	(4.1)	(4)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	0.8	1.1
Net Periodic Benefit Cost (Credit)	0.9	1.3
Pension Plans [Member] | Southwestern Electric Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	2.1	2.3
Interest Cost	3.1	2.9
Expected Return on Plan Assets	(4.4)	(4.4)
Amortization of Prior Service Cost (Credit)	0	0
Amortization of Net Actuarial Loss	0.9	1.3
Net Periodic Benefit Cost (Credit)	1.7	2.1
Other Postretirement Benefit Plans [Member]
Components of Net Periodic Benefit Cost
Service Cost	2.4	2.9
Interest Cost	12.6	11.8
Expected Return on Plan Assets	(23.4)	(25.5)
Amortization of Prior Service Cost (Credit)	(17.3)	(17.3)
Amortization of Net Actuarial Loss	5.5	2.6
Net Periodic Benefit Cost (Credit)	(20.2)	(25.5)
Other Postretirement Benefit Plans [Member] | AEP Texas Inc. [Member]
Components of Net Periodic Benefit Cost
Service Cost	0.2	0.3
Interest Cost	1	0.9
Expected Return on Plan Assets	(2)	(2.1)
Amortization of Prior Service Cost (Credit)	(1.5)	(1.5)
Amortization of Net Actuarial Loss	0.5	0.2
Net Periodic Benefit Cost (Credit)	(1.8)	(2.2)
Other Postretirement Benefit Plans [Member] | Appalachian Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	0.3	0.3
Interest Cost	2.2	2
Expected Return on Plan Assets	(3.7)	(4)
Amortization of Prior Service Cost (Credit)	(2.5)	(2.5)
Amortization of Net Actuarial Loss	0.9	0.5
Net Periodic Benefit Cost (Credit)	(2.8)	(3.7)
Other Postretirement Benefit Plans [Member] | Indiana Michigan Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	0.3	0.4
Interest Cost	1.5	1.4
Expected Return on Plan Assets	(2.8)	(3.1)
Amortization of Prior Service Cost (Credit)	(2.4)	(2.4)
Amortization of Net Actuarial Loss	0.7	0.3
Net Periodic Benefit Cost (Credit)	(2.7)	(3.4)
Other Postretirement Benefit Plans [Member] | Ohio Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	0.2	0.2
Interest Cost	1.4	1.3
Expected Return on Plan Assets	(2.7)	(3)
Amortization of Prior Service Cost (Credit)	(1.7)	(1.7)
Amortization of Net Actuarial Loss	0.6	0.3
Net Periodic Benefit Cost (Credit)	(2.2)	(2.9)
Other Postretirement Benefit Plans [Member] | Public Service Co Of Oklahoma [Member]
Components of Net Periodic Benefit Cost
Service Cost	0.2	0.2
Interest Cost	0.7	0.6
Expected Return on Plan Assets	(1.3)	(1.4)
Amortization of Prior Service Cost (Credit)	(1.1)	(1)
Amortization of Net Actuarial Loss	0.3	0.1
Net Periodic Benefit Cost (Credit)	(1.2)	(1.5)
Other Postretirement Benefit Plans [Member] | Southwestern Electric Power Co [Member]
Components of Net Periodic Benefit Cost
Service Cost	0.2	0.3
Interest Cost	0.8	0.7
Expected Return on Plan Assets	(1.5)	(1.6)
Amortization of Prior Service Cost (Credit)	(1.3)	(1.3)
Amortization of Net Actuarial Loss	0.3	0.1
Net Periodic Benefit Cost (Credit)	$ (1.5)	$ (1.8)

Business Segments (Details)

Business Segments (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019		Mar. 31, 2018		Dec. 31, 2018
Revenue from Contracts with Customers		$ 4,056.8		$ 4,048.3
Reportable Segment Information
Sales to AEP Affiliates		0		0
TOTAL REVENUES		4,056.8		4,048.3
Interest Expense		255.8		234
Income Tax Expense (Benefit)		44.5		102
NET INCOME (LOSS)		574.1		456.7
Balance Sheet Information
Total Property, Plant and Equipment		74,151.2				$ 73,085.2
Accumulated Depreciation and Amortization		18,182.6				17,986.1
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		55,968.6				55,099.1
Total Assets		70,722				68,802.8
Long-term Debt Due Within One Year		1,528.5				1,698.5
Long-term Debt - Affiliated		0				0
Long-term Debt		22,898.2				21,648.2
Total Long-term Debt Outstanding		24,426.7				23,346.7
Vertically Integrated Utilities [Member]
Reportable Segment Information
Sales to AEP Affiliates		31		26.5
TOTAL REVENUES		2,403.3		2,408
NET INCOME (LOSS)		303.6		232.8
Balance Sheet Information
Total Property, Plant and Equipment		45,684.3				45,365.1
Accumulated Depreciation and Amortization		13,944.5				13,822.5
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		31,739.8				31,542.6
Total Assets		40,085.7				38,874.3
Long-term Debt Due Within One Year		912.1				1,066.3
Long-term Debt - Affiliated		50				50
Long-term Debt		11,999.5				11,442.7
Total Long-term Debt Outstanding		12,961.6				12,559
Transmission And Distribution Companies [Member]
Reportable Segment Information
Sales to AEP Affiliates		42.2		21.2
TOTAL REVENUES		1,222		1,162.4
NET INCOME (LOSS)		156.5		125.4
Balance Sheet Information
Total Property, Plant and Equipment		18,526.1				18,126.7
Accumulated Depreciation and Amortization		3,856.1				3,833.7
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		14,670				14,293
Total Assets		17,419				17,083.4
Long-term Debt Due Within One Year		533.3				549.1
Long-term Debt - Affiliated		0				0
Long-term Debt		4,938.6				5,048.8
Total Long-term Debt Outstanding		5,471.9				5,597.9
AEP Transmission Holdco [Member]
Reportable Segment Information
TOTAL REVENUES		256.4		205.5
Balance Sheet Information
Total Property, Plant and Equipment		8,973.2				8,659.5
Accumulated Depreciation and Amortization		318.8				282.8
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		8,654.4				8,376.7
Total Assets		9,790.2				9,543.7
Long-term Debt Due Within One Year		85				85
Long-term Debt - Affiliated		0				0
Long-term Debt		2,895.3				2,888.6
Total Long-term Debt Outstanding		2,980.3				2,973.6
Transmission Operations [Member]
Reportable Segment Information
Sales to AEP Affiliates		195.2		164.4
TOTAL REVENUES		256.4		205.5
NET INCOME (LOSS)		125.2		104.8
Generation And Marketing [Member]
Reportable Segment Information
Sales to AEP Affiliates		42.1		27.6
TOTAL REVENUES		481.8		505.1
NET INCOME (LOSS)		39.2		18.1
Balance Sheet Information
Total Property, Plant and Equipment		915.6				893.3
Accumulated Depreciation and Amortization		58.7				47
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		856.9				846.3
Total Assets		1,960.1				1,979.7
Long-term Debt Due Within One Year		0				0.1
Long-term Debt - Affiliated		32.2				32.2
Long-term Debt		(0.3)				(0.3)
Total Long-term Debt Outstanding		31.9				32
Other Segments [Member]
Reportable Segment Information
Sales to AEP Affiliates	[1]	21.7		17
TOTAL REVENUES	[1]	25.5		24
NET INCOME (LOSS)	[1]	(50.4)		(24.4)
Balance Sheet Information
Total Property, Plant and Equipment	[1]	406.4				395.2
Accumulated Depreciation and Amortization	[1]	190.9				186.6
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	[1]	215.5				208.6
Total Assets	[1],[2]	4,341.2				4,036.5
Long-term Debt Due Within One Year	[1],[3]	(1.9)				(2)
Long-term Debt - Affiliated	[1]	0				0
Long-term Debt	[1]	3,065.1				2,268.4
Total Long-term Debt Outstanding	[1],[3]	3,063.2				2,266.4
Consolidation, Eliminations [Member]
Revenue from Contracts with Customers		0		0
Reportable Segment Information
Sales to AEP Affiliates		(332.2)		(256.7)
TOTAL REVENUES		(332.2)		(256.7)
NET INCOME (LOSS)		0		0
Balance Sheet Information
Total Property, Plant and Equipment	[4]	(354.4)				(354.6)
Accumulated Depreciation and Amortization	[4]	(186.4)				(186.5)
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	[4]	(168)				(168.1)
Total Assets	[4],[5]	(2,874.2)				(2,714.8)
Long-term Debt Due Within One Year		0				0
Long-term Debt - Affiliated		(82.2)				(82.2)
Long-term Debt		0				0
Total Long-term Debt Outstanding		(82.2)				(82.2)
AEP Transmission Co [Member]
Revenue from Contracts with Customers		245.2		187	[6]
Reportable Segment Information
Sales to AEP Affiliates		193.2		160.7	[7]
TOTAL REVENUES		243.5		191.7	[6],[7]
Investment Income, Interest and Dividend		0.7		0.4	[7]
Interest Expense		21.7		20.3	[7]
Income Tax Expense (Benefit)		27.6		22	[7]
NET INCOME (LOSS)		104.3		84.1	[7]
Balance Sheet Information
Total Property, Plant and Equipment		8,567.2				8,268.1
Accumulated Depreciation and Amortization		306.7				271.9
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		8,260.5				7,996.2
Notes Receivable, Related Parties		0				0
Total Assets		8,616.1				8,394.1
Long-term Debt Due Within One Year		85				85
Long-term Debt		2,738.4				2,738
Total Long-term Debt Outstanding		2,823.4				2,823
AEP Transmission Co [Member] | State Transcos [Member]
Reportable Segment Information
Sales to AEP Affiliates		193.2		160.7	[7]
TOTAL REVENUES		243.5		191.7	[7]
Investment Income, Interest and Dividend		0.2		0.2	[7]
Interest Expense		21.7		20.3	[7]
Income Tax Expense (Benefit)		27.6		21.7	[7]
NET INCOME (LOSS)		104.2		84.1	[7]
Balance Sheet Information
Total Property, Plant and Equipment		8,567.2				8,268.1
Accumulated Depreciation and Amortization		306.7				271.9
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		8,260.5				7,996.2
Notes Receivable, Related Parties		0				0
Total Assets		8,584				8,406.8
Total Long-term Debt Outstanding		2,850				2,850
AEP Transmission Co [Member] | AEPTCo Parent [Member]
Reportable Segment Information
Sales to AEP Affiliates		0		0
TOTAL REVENUES		0		0
Investment Income, Interest and Dividend		28.4		25
Interest Expense		27.9		24.8
Income Tax Expense (Benefit)		0		0.3
NET INCOME (LOSS)	[8]	0.1		0
Balance Sheet Information
Total Property, Plant and Equipment		0				0
Accumulated Depreciation and Amortization		0				0
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		0				0
Notes Receivable, Related Parties		2,823.4				2,823
Total Assets	[9]	2,928.1				2,857.1
Total Long-term Debt Outstanding		2,823.4				2,823
AEP Transmission Co [Member] | Consolidation, Eliminations [Member]
Revenue from Contracts with Customers		0		0
Reportable Segment Information
Sales to AEP Affiliates		0		0
TOTAL REVENUES		0		0
Investment Income, Interest and Dividend	[10]	(27.9)		(24.8)
Interest Expense	[10]	(27.9)		(24.8)
Income Tax Expense (Benefit)		0		0
NET INCOME (LOSS)		0		0
Balance Sheet Information
Total Property, Plant and Equipment		0				0
Accumulated Depreciation and Amortization		0				0
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET		0				0
Notes Receivable, Related Parties	[11]	(2,823.4)				(2,823)
Total Assets	[12]	(2,896)				(2,869.8)
Total Long-term Debt Outstanding	[11]	(2,850)				$ (2,850)
Transmission and Distribution Utilities Revenues [Member]
Revenue from Contracts with Customers		1,179.8		1,141.2
Transmission and Distribution Utilities Revenues [Member] | Transmission And Distribution Companies [Member]
Revenue from Contracts with Customers		1,179.8		1,141.2
Electric Transmission [Member] | Transmission Operations [Member]
Revenue from Contracts with Customers		61.2		41.1
Electric Transmission [Member] | AEP Transmission Co [Member]
Revenue from Contracts with Customers		50.3		30.9	[7]
Electric Transmission [Member] | AEP Transmission Co [Member] | State Transcos [Member]
Revenue from Contracts with Customers		50.3		30.9	[7]
Electric Transmission [Member] | AEP Transmission Co [Member] | AEPTCo Parent [Member]
Revenue from Contracts with Customers		0		0
Generation & Marketing Revenues [Member]
Revenue from Contracts with Customers		439.7		477.5
Generation & Marketing Revenues [Member] | Generation And Marketing [Member]
Revenue from Contracts with Customers		439.7		477.5
Other Revenues [Member]
Revenue from Contracts with Customers		65		48.1
Reportable Segment Information
TOTAL REVENUES		50.8	[13]	28.5	[14]
Other Revenues [Member] | Vertically Integrated Utilities [Member]
Reportable Segment Information
TOTAL REVENUES		0	[13]	5.5	[14]
Other Revenues [Member] | Transmission And Distribution Companies [Member]
Reportable Segment Information
TOTAL REVENUES		39.4	[13]	21.7	[14]
Other Revenues [Member] | AEP Transmission Holdco [Member]
Reportable Segment Information
TOTAL REVENUES		0	[13]	0	[14]
Other Revenues [Member] | Generation And Marketing [Member]
Reportable Segment Information
TOTAL REVENUES		9.2	[13]	21	[14]
Other Revenues [Member] | Other Segments [Member]
Revenue from Contracts with Customers	[1]	3.8		7
Reportable Segment Information
TOTAL REVENUES		2.2	[13]	2	[14]
Other Revenues [Member] | Consolidation, Eliminations [Member]
Reportable Segment Information
TOTAL REVENUES		0	[13]	(21.7)	[14]
Other Revenues [Member] | AEP Transmission Co [Member]
Revenue from Contracts with Customers		0		0.1	[7]
Reportable Segment Information
TOTAL REVENUES		0	[15]	0	[6],[16]
Other Revenues [Member] | AEP Transmission Co [Member] | State Transcos [Member]
Revenue from Contracts with Customers	[7]			0.1
Other Revenues [Member] | AEP Transmission Co [Member] | AEPTCo Parent [Member]
Revenue from Contracts with Customers				0
Electricity [Member]
Revenue from Contracts with Customers		2,372.3		2,381.5
Electricity [Member] | Vertically Integrated Utilities [Member]
Revenue from Contracts with Customers		$ 2,372.3		$ 2,381.5
[1]	Corporate and Other primarily includes the purchasing of receivables from certain AEP utility subsidiaries. This segment also includes Parent’s guarantee revenue received from affiliates, investment income, interest income and interest expense and other nonallocated costs.
[2]	Includes elimination of AEP Parent’s investments in wholly-owned subsidiary companies.
[3]	Amounts reflect the impact of fair value hedge accounting. See “Accounting for Fair Value Hedging Strategies” section of Note 10 for additional information.
[4]	Includes eliminations due to an intercompany finance lease.
[5]	Reconciling Adjustments for Total Assets primarily include elimination of intercompany advances to affiliates and intercompany accounts receivable.
[6]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[7]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[8]	Includes the elimination of AEPTCo Parent’s equity earnings in the State Transcos.
[9]	Includes the elimination of AEPTCo Parent’s investments in State Transcos.
[10]	Elimination of intercompany interest income/interest expense on affiliated debt arrangement.
[11]	Elimination of intercompany debt.
[12]	Primarily relates to the elimination of Notes Receivable from the State Transcos.
[13]	Amounts include affiliated and nonaffiliated revenues.
[14]	Amounts include affiliated and nonaffiliated revenues.
[15]	Amounts include affiliated and nonaffiliated revenues.
[16]	Amounts include affiliated and nonaffiliated revenues.

Derivatives and Hedging (Detail

Derivatives and Hedging (Details) gal in Millions, MWh in Millions, MMBTU in Millions		3 Months Ended			12 Months Ended
		Mar. 31, 2019USD ($)MWhMMBTUgal		Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)MWhMMBTUgal
Carrying Amount of Hedged Asset (Liability)	[1]	$ (489,600,000)			$ (478,300,000)
Derivative, Gain (Loss) on Derivative, Net	[2]	11,100,000		$ (14,500,000)
Gain (Loss) on Fair Value Portion of Long Term Debt	[2]	(11,100,000)		14,500,000
Cash Collateral Netting
Cash Collateral Received Netted Against Risk Management Assets		9,000,000			18,000,000
Cash Collateral Paid Netted Against Risk Management Liabilities		9,000,000			4,000,000
Fair Value of Derivative Instruments
Current Risk Management Assets		93,900,000			162,800,000
Long-term Risk Management Assets		250,400,000			254,000,000
Total Assets		344,300,000			416,800,000
Current Risk Management Liabilities		63,400,000			55,000,000
Long-term Risk Management Liabilities		267,900,000			263,400,000
Derivative Liability		331,300,000			318,400,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(24,900,000)		109,300,000
Collateral Triggering Events
Liabilities for Contracts with Cross Default Provisions Prior to Contractual Netting Arrangements		219,200,000			225,500,000
Amount of Cash Collateral Posted		3,800,000			1,800,000
Additional Settlement Liability if Cross Default Provision is Triggered		$ 189,000,000			181,000,000
Derivatives and Hedging (Textuals)
Maximum Term for Exposure to Variability of Future Cash Flows		177 months
Cumulative Fair Value Hedging Adjustment in the Carrying Amount of the Hedged Asset (Liability)	[1]	$ 6,300,000			17,400,000
AEP Texas Inc. [Member]
Fair Value of Derivative Instruments
Current Risk Management Liabilities		200,000			200,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		400,000		100,000
Appalachian Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets		12,900,000			57,200,000
Long-term Risk Management Assets		300,000			900,000
Current Risk Management Liabilities		6,100,000			400,000
Long-term Risk Management Liabilities		200,000			200,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(34,000,000)		68,500,000
Collateral Triggering Events
Liabilities for Contracts with Cross Default Provisions Prior to Contractual Netting Arrangements		1,400,000			900,000
Amount of Cash Collateral Posted		0			0
Additional Settlement Liability if Cross Default Provision is Triggered		100,000			0
Indiana Michigan Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets		4,400,000			8,600,000
Long-term Risk Management Assets		100,000			600,000
Current Risk Management Liabilities		300,000			300,000
Long-term Risk Management Liabilities		100,000			100,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		7,200,000		1,500,000
Collateral Triggering Events
Liabilities for Contracts with Cross Default Provisions Prior to Contractual Netting Arrangements		800,000			500,000
Amount of Cash Collateral Posted		0			0
Additional Settlement Liability if Cross Default Provision is Triggered		100,000			0
Ohio Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Liabilities		6,900,000			5,800,000
Long-term Risk Management Liabilities		99,400,000			93,800,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(9,100,000)		31,600,000
Public Service Co Of Oklahoma [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets		5,000,000			10,400,000
Current Risk Management Liabilities		700,000			1,000,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		6,700,000		12,100,000
Southwestern Electric Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets		2,000,000			4,800,000
Current Risk Management Liabilities		200,000			400,000
Long-term Risk Management Liabilities		1,900,000			2,200,000
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		4,600,000		(1,100,000)
Collateral Triggering Events
Liabilities for Contracts with Cross Default Provisions Prior to Contractual Netting Arrangements		2,000,000			2,300,000
Amount of Cash Collateral Posted		0			0
Additional Settlement Liability if Cross Default Provision is Triggered		1,900,000			2,300,000
Risk Management Contracts [Member]
Fair Value of Derivative Instruments
Total Assets	[3]	324,100,000	[4]		382,700,000	[5]
Derivative Liability	[3]	249,000,000	[4]		242,100,000	[5]
Risk Management Contracts [Member] | AEP Texas Inc. [Member]
Fair Value of Derivative Instruments
Derivative Liability	[3]	200,000			200,000
Risk Management Contracts [Member] | Appalachian Power Co [Member]
Fair Value of Derivative Instruments
Total Assets	[3],[6]	13,200,000			58,100,000
Derivative Liability	[3],[6]	6,300,000			600,000
Risk Management Contracts [Member] | Indiana Michigan Power Co [Member]
Fair Value of Derivative Instruments
Total Assets	[3],[6]	4,500,000			9,200,000
Derivative Liability	[3],[6]	400,000			400,000
Risk Management Contracts [Member] | Ohio Power Co [Member]
Fair Value of Derivative Instruments
Derivative Liability	[3],[6]	106,300,000			99,600,000
Risk Management Contracts [Member] | Public Service Co Of Oklahoma [Member]
Fair Value of Derivative Instruments
Total Assets	[3],[6]	5,000,000			10,400,000
Derivative Liability	[3],[6]	700,000			1,000,000
Risk Management Contracts [Member] | Southwestern Electric Power Co [Member]
Fair Value of Derivative Instruments
Total Assets	[3],[6]	2,000,000			4,800,000
Derivative Liability	[3],[6]	2,100,000			2,600,000
Commodity [Member]
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		(52,100,000)			(23,000,000)
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		1,600,000			10,400,000
Derivatives and Hedging (Textuals)
Cross Default Provisions Maximum Third Party Obligation Amount		50,000,000			50,000,000
Commodity [Member] | Risk Management Contracts [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	228,300,000			397,500,000
Long-term Risk Management Assets	[7]	279,000,000			276,400,000
Total Assets	[7]	507,300,000			673,900,000
Current Risk Management Liabilities	[7]	195,900,000			293,800,000
Long-term Risk Management Liabilities	[7]	236,600,000			225,700,000
Derivative Liability	[7]	432,500,000			519,500,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	74,800,000			154,400,000
Commodity [Member] | Risk Management Contracts [Member] | AEP Texas Inc. [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	0			0
Long-term Risk Management Assets	[7]	0			0
Total Assets	[7]	0			0
Current Risk Management Liabilities	[7]	200,000			700,000
Long-term Risk Management Liabilities	[7]	0			0
Derivative Liability	[7]	200,000			700,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	(200,000)			(700,000)
Commodity [Member] | Risk Management Contracts [Member] | Appalachian Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	40,500,000			114,400,000
Long-term Risk Management Assets	[7]	3,900,000			3,100,000
Total Assets	[7]	44,400,000			117,500,000
Current Risk Management Liabilities	[7]	33,500,000			56,700,000
Long-term Risk Management Liabilities	[7]	3,700,000			2,400,000
Derivative Liability	[7]	37,200,000			59,100,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	7,200,000			58,400,000
Commodity [Member] | Risk Management Contracts [Member] | Indiana Michigan Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	22,000,000			50,400,000
Long-term Risk Management Assets	[7]	2,300,000			2,000,000
Total Assets	[7]	24,300,000			52,400,000
Current Risk Management Liabilities	[7]	17,600,000			41,100,000
Long-term Risk Management Liabilities	[7]	2,200,000			1,600,000
Derivative Liability	[7]	19,800,000			42,700,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	4,500,000			9,700,000
Commodity [Member] | Risk Management Contracts [Member] | Ohio Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	0			0
Long-term Risk Management Assets	[7]	0			0
Total Assets	[7]	0			0
Current Risk Management Liabilities	[7]	6,900,000			6,400,000
Long-term Risk Management Liabilities	[7]	99,400,000			93,800,000
Derivative Liability	[7]	106,300,000			100,200,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	(106,300,000)			(100,200,000)
Commodity [Member] | Risk Management Contracts [Member] | Public Service Co Of Oklahoma [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	5,400,000			10,900,000
Long-term Risk Management Assets	[7]	0			0
Total Assets	[7]	5,400,000			10,900,000
Current Risk Management Liabilities	[7]	1,100,000			1,700,000
Long-term Risk Management Liabilities	[7]	0			0
Derivative Liability	[7]	1,100,000			1,700,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	4,300,000			9,200,000
Commodity [Member] | Risk Management Contracts [Member] | Southwestern Electric Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	2,300,000			5,600,000
Long-term Risk Management Assets	[7]	0			0
Total Assets	[7]	2,300,000			5,600,000
Current Risk Management Liabilities	[7]	500,000			1,500,000
Long-term Risk Management Liabilities	[7]	1,900,000			2,200,000
Derivative Liability	[7]	2,400,000			3,700,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	(100,000)			1,900,000
Commodity [Member] | Hedging Contracts [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	20,800,000			28,500,000
Long-term Risk Management Assets	[7]	7,400,000			16,000,000
Total Assets	[7]	28,200,000			44,500,000
Current Risk Management Liabilities	[7]	15,400,000			13,200,000
Long-term Risk Management Liabilities	[7]	68,600,000			56,100,000
Derivative Liability	[7]	84,000,000			69,300,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	(55,800,000)			(24,800,000)
Interest Rate [Member]
Commodity:
Derivative, Notional Amount		500,000,000			500,000,000
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		(12,400,000)			(12,600,000)
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		(1,500,000)			(1,100,000)
Interest Rate [Member] | AEP Texas Inc. [Member]
Commodity:
Derivative, Notional Amount		0			0
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		(4,100,000)			(4,400,000)
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		(1,100,000)			(1,100,000)
Interest Rate [Member] | Appalachian Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		1,600,000			1,800,000
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		900,000			900,000
Interest Rate [Member] | Indiana Michigan Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		(11,100,000)			(11,500,000)
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		(1,600,000)			(1,600,000)
Interest Rate [Member] | Ohio Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		700,000			1,000,000
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		600,000			1,000,000
Interest Rate [Member] | Public Service Co Of Oklahoma [Member]
Commodity:
Derivative, Notional Amount		0			0
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		1,900,000			2,100,000
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		1,000,000			1,000,000
Interest Rate [Member] | Southwestern Electric Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Impact of Cash Flow Hedges on the Condensed Balance Sheet
AOCI Gain (Loss) Net of Tax		(2,900,000)			(3,300,000)
Portion Expected to be Reclassified to Net Income During the Next Twelve Months		(1,500,000)			(1,500,000)
Interest Rate [Member] | Hedging Contracts [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[7]	0			0
Long-term Risk Management Assets	[7]	0			0
Total Assets	[7]	0			0
Current Risk Management Liabilities	[7]	1,900,000			2,000,000
Long-term Risk Management Liabilities	[7]	4,400,000			15,400,000
Derivative Liability	[7]	6,300,000			17,400,000
Total MTM Derivative Contract Net Assets (Liabilities)	[7]	(6,300,000)			(17,400,000)
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets		249,100,000			426,000,000
Long-term Risk Management Assets		286,400,000			292,400,000
Total Assets		535,500,000			718,400,000
Current Risk Management Liabilities		213,200,000			309,000,000
Long-term Risk Management Liabilities		309,600,000			297,200,000
Derivative Liability		522,800,000			606,200,000
Total MTM Derivative Contract Net Assets (Liabilities)		12,700,000			112,200,000
Gross Amounts Offset in the Statement of Financial Position [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	(155,200,000)			(263,200,000)
Long-term Risk Management Assets	[8]	(36,000,000)			(38,400,000)
Total Assets	[8]	(191,200,000)			(301,600,000)
Current Risk Management Liabilities	[8]	(149,800,000)			(254,000,000)
Long-term Risk Management Liabilities	[8]	(41,700,000)			(33,800,000)
Derivative Liability	[8]	(191,500,000)			(287,800,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	300,000			(13,800,000)
Gross Amounts Offset in the Statement of Financial Position [Member] | AEP Texas Inc. [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	0			0
Long-term Risk Management Assets	[8]	0			0
Total Assets	[8]	0			0
Current Risk Management Liabilities	[8]	0			(500,000)
Long-term Risk Management Liabilities	[8]	0			0
Derivative Liability	[8]	0			(500,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	0			500,000
Gross Amounts Offset in the Statement of Financial Position [Member] | Appalachian Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	(27,600,000)			(57,200,000)
Long-term Risk Management Assets	[8]	(3,600,000)			(2,200,000)
Total Assets	[8]	(31,200,000)			(59,400,000)
Current Risk Management Liabilities	[8]	(27,400,000)			(56,300,000)
Long-term Risk Management Liabilities	[8]	(3,500,000)			(2,200,000)
Derivative Liability	[8]	(30,900,000)			(58,500,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	(300,000)			(900,000)
Gross Amounts Offset in the Statement of Financial Position [Member] | Indiana Michigan Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	(17,600,000)			(41,800,000)
Long-term Risk Management Assets	[8]	(2,200,000)			(1,400,000)
Total Assets	[8]	(19,800,000)			(43,200,000)
Current Risk Management Liabilities	[8]	(17,300,000)			(40,800,000)
Long-term Risk Management Liabilities	[8]	(2,100,000)			(1,500,000)
Derivative Liability	[8]	(19,400,000)			(42,300,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	(400,000)			(900,000)
Gross Amounts Offset in the Statement of Financial Position [Member] | Ohio Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	0			0
Long-term Risk Management Assets	[8]	0			0
Total Assets	[8]	0			0
Current Risk Management Liabilities	[8]	0			(600,000)
Long-term Risk Management Liabilities	[8]	0			0
Derivative Liability	[8]	0			(600,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	0			600,000
Gross Amounts Offset in the Statement of Financial Position [Member] | Public Service Co Of Oklahoma [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	(400,000)			(500,000)
Long-term Risk Management Assets	[8]	0			0
Total Assets	[8]	(400,000)			(500,000)
Current Risk Management Liabilities	[8]	(400,000)			(700,000)
Long-term Risk Management Liabilities	[8]	0			0
Derivative Liability	[8]	(400,000)			(700,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	0			200,000
Gross Amounts Offset in the Statement of Financial Position [Member] | Southwestern Electric Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[8]	(300,000)			(800,000)
Long-term Risk Management Assets	[8]	0			0
Total Assets	[8]	(300,000)			(800,000)
Current Risk Management Liabilities	[8]	(300,000)			(1,100,000)
Long-term Risk Management Liabilities	[8]	0			0
Derivative Liability	[8]	(300,000)			(1,100,000)
Total MTM Derivative Contract Net Assets (Liabilities)	[8]	0			300,000
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	93,900,000			162,800,000
Long-term Risk Management Assets	[9]	250,400,000			254,000,000
Total Assets	[9]	344,300,000			416,800,000
Current Risk Management Liabilities	[9]	63,400,000			55,000,000
Long-term Risk Management Liabilities	[9]	267,900,000			263,400,000
Derivative Liability	[9]	331,300,000			318,400,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	13,000,000			98,400,000
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | AEP Texas Inc. [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	0			0
Long-term Risk Management Assets	[9]	0			0
Total Assets	[9]	0			0
Current Risk Management Liabilities	[9]	200,000			200,000
Long-term Risk Management Liabilities	[9]	0			0
Derivative Liability	[9]	200,000			200,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	(200,000)			(200,000)
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Appalachian Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	12,900,000			57,200,000
Long-term Risk Management Assets	[9]	300,000			900,000
Total Assets	[9]	13,200,000			58,100,000
Current Risk Management Liabilities	[9]	6,100,000			400,000
Long-term Risk Management Liabilities	[9]	200,000			200,000
Derivative Liability	[9]	6,300,000			600,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	6,900,000			57,500,000
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Indiana Michigan Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	4,400,000			8,600,000
Long-term Risk Management Assets	[9]	100,000			600,000
Total Assets	[9]	4,500,000			9,200,000
Current Risk Management Liabilities	[9]	300,000			300,000
Long-term Risk Management Liabilities	[9]	100,000			100,000
Derivative Liability	[9]	400,000			400,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	4,100,000			8,800,000
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Ohio Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	0			0
Long-term Risk Management Assets	[9]	0			0
Total Assets	[9]	0			0
Current Risk Management Liabilities	[9]	6,900,000			5,800,000
Long-term Risk Management Liabilities	[9]	99,400,000			93,800,000
Derivative Liability	[9]	106,300,000			99,600,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	(106,300,000)			(99,600,000)
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Public Service Co Of Oklahoma [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	5,000,000			10,400,000
Long-term Risk Management Assets	[9]	0			0
Total Assets	[9]	5,000,000			10,400,000
Current Risk Management Liabilities	[9]	700,000			1,000,000
Long-term Risk Management Liabilities	[9]	0			0
Derivative Liability	[9]	700,000			1,000,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	4,300,000			9,400,000
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Southwestern Electric Power Co [Member]
Fair Value of Derivative Instruments
Current Risk Management Assets	[9]	2,000,000			4,800,000
Long-term Risk Management Assets	[9]	0			0
Total Assets	[9]	2,000,000			4,800,000
Current Risk Management Liabilities	[9]	200,000			400,000
Long-term Risk Management Liabilities	[9]	1,900,000			2,200,000
Derivative Liability	[9]	2,100,000			2,600,000
Total MTM Derivative Contract Net Assets (Liabilities)	[9]	$ (100,000)			$ 2,200,000
Power [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		310.4			371.1
Power [Member] | AEP Texas Inc. [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		0			0
Power [Member] | Appalachian Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		43.9			66.4
Power [Member] | Indiana Michigan Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		25.9			40.9
Power [Member] | Ohio Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		7.6			7.8
Power [Member] | Public Service Co Of Oklahoma [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		7.8			15.2
Power [Member] | Southwestern Electric Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MWh		2			4.5
Natural Gas [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		80.6			87.9
Natural Gas [Member] | AEP Texas Inc. [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		0			0
Natural Gas [Member] | Appalachian Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		4			4
Natural Gas [Member] | Indiana Michigan Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		2.3			2.3
Natural Gas [Member] | Ohio Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		0			0
Natural Gas [Member] | Public Service Co Of Oklahoma [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		0			0
Natural Gas [Member] | Southwestern Electric Power Co [Member]
Commodity:
Derivative, Energy Notional Amount | MMBTU		14.3			15.2
Heating Oil and Gasoline [Member]
Commodity:
Derivative, Volume Notional Amount | gal		5.4			7.4
Heating Oil and Gasoline [Member] | AEP Texas Inc. [Member]
Commodity:
Derivative, Volume Notional Amount | gal		1.1			1.5
Heating Oil and Gasoline [Member] | Appalachian Power Co [Member]
Commodity:
Derivative, Volume Notional Amount | gal		1			1.4
Heating Oil and Gasoline [Member] | Indiana Michigan Power Co [Member]
Commodity:
Derivative, Volume Notional Amount | gal		0.5			0.7
Heating Oil and Gasoline [Member] | Ohio Power Co [Member]
Commodity:
Derivative, Volume Notional Amount | gal		1.3			1.8
Heating Oil and Gasoline [Member] | Public Service Co Of Oklahoma [Member]
Commodity:
Derivative, Volume Notional Amount | gal		0.5			0.7
Heating Oil and Gasoline [Member] | Southwestern Electric Power Co [Member]
Commodity:
Derivative, Volume Notional Amount | gal		0.6			0.8
Interest Rate Contract [Member]
Commodity:
Derivative, Notional Amount		$ 33,800,000			$ 37,700,000
Interest Rate Contract [Member] | AEP Texas Inc. [Member]
Commodity:
Derivative, Notional Amount		0			0
Interest Rate Contract [Member] | Appalachian Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Interest Rate Contract [Member] | Indiana Michigan Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Interest Rate Contract [Member] | Ohio Power Co [Member]
Commodity:
Derivative, Notional Amount		0			0
Interest Rate Contract [Member] | Public Service Co Of Oklahoma [Member]
Commodity:
Derivative, Notional Amount		0			0
Interest Rate Contract [Member] | Southwestern Electric Power Co [Member]
Commodity:
Derivative, Notional Amount		0			$ 0
Vertically Integrated Utilities Revenues [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		300,000		(5,500,000)
Vertically Integrated Utilities Revenues [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Vertically Integrated Utilities Revenues [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Vertically Integrated Utilities Revenues [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Vertically Integrated Utilities Revenues [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Vertically Integrated Utilities Revenues [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Vertically Integrated Utilities Revenues [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Generation & Marketing Revenues [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		2,700,000		(15,100,000)
Generation & Marketing Revenues [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Generation & Marketing Revenues [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Generation & Marketing Revenues [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Generation & Marketing Revenues [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Generation & Marketing Revenues [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Generation & Marketing Revenues [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Electric Generation, Transmission and Distribution Revenues [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Electric Generation, Transmission and Distribution Revenues [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Electric Generation, Transmission and Distribution Revenues [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		(300,000)
Electric Generation, Transmission and Distribution Revenues [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		300,000		(5,100,000)
Electric Generation, Transmission and Distribution Revenues [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Electric Generation, Transmission and Distribution Revenues [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Electric Generation, Transmission and Distribution Revenues [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		100,000		0
Purchased Electricity for Resale [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		1,400,000		4,900,000
Purchased Electricity for Resale [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Purchased Electricity for Resale [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		4,600,000
Purchased Electricity for Resale [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		200,000
Purchased Electricity for Resale [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Purchased Electricity for Resale [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Purchased Electricity for Resale [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Other Operation Expense [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(400,000)		300,000
Other Operation Expense [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		100,000
Other Operation Expense [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		0
Other Operation Expense [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Other Operation Expense [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		100,000
Other Operation Expense [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Other Operation Expense [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Maintenance Expense [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(500,000)		400,000
Maintenance Expense [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		100,000
Maintenance Expense [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		100,000
Maintenance Expense [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Maintenance Expense [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		100,000
Maintenance Expense [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		0		0
Maintenance Expense [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts		(100,000)		0
Regulatory Assets [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	(6,400,000)		37,300,000
Regulatory Assets [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	600,000		0
Regulatory Assets [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	(2,100,000)		0
Regulatory Assets [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	300,000		6,200,000
Regulatory Assets [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	(8,900,000)		31,400,000
Regulatory Assets [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	500,000		0
Regulatory Assets [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	(100,000)		(300,000)
Regulatory Liabilities [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	(22,000,000)		87,000,000
Regulatory Liabilities [Member] | AEP Texas Inc. [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	0		(100,000)
Regulatory Liabilities [Member] | Appalachian Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	(31,700,000)		64,100,000
Regulatory Liabilities [Member] | Indiana Michigan Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	6,600,000		200,000
Regulatory Liabilities [Member] | Ohio Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	0		0
Regulatory Liabilities [Member] | Public Service Co Of Oklahoma [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	6,200,000		12,100,000
Regulatory Liabilities [Member] | Southwestern Electric Power Co [Member]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Amount of Gain (Loss) Recognized on Risk Management Contracts	[10]	$ 4,700,000		$ (800,000)
[1]	Amounts included on the balance sheets within Long-term Debt Due within One Year and Long-term Debt, respectively.
[2]	Gain (Loss) is included in Interest Expense on the statements of income.
[3]	Amounts in “Other’’ column primarily represent counterparty netting of risk management and hedging contracts and associated cash collateral under the accounting guidance for “Derivatives and Hedging.”
[4]	The March 31, 2019 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(7) million in 2019, $2 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $27 million in 2019, $42 million in periods 2020-2022, $23 million in periods 2023-2024 and $(13) million
[5]	The December 31, 2018 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(4) million in 2019, $1 million in periods 2020-2022, $1 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $108 million in 2019, $37 million in periods 2020-2022, $23 million in periods 2023-2024 and $(12) million
[6]	Substantially comprised of power contracts for the Registrant Subsidiaries.
[7]	Derivative instruments within these categories are reported gross.  These instruments are subject to master netting agreements and are presented on the balance sheets on a net basis in accordance with the accounting guidance for “Derivatives and Hedging.”
[8]	Amounts include counterparty netting of risk management and hedging contracts and associated cash collateral in accordance with the accounting guidance for “Derivatives and Hedging.”
[9]	All derivative contracts subject to a master netting arrangement or similar agreement are offset in the statement of financial position.
[10]	Represents realized and unrealized gains and losses subject to regulatory accounting treatment recorded as either current or noncurrent on the balance sheets.

Fair Value Long-term Debt, Othe

Fair Value Long-term Debt, Other Temporary Investments, Nuclear Trusts (Details) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
		Mar. 31, 2019		Mar. 31, 2018	Dec. 31, 2018
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		$ 24,426.7			$ 23,346.7
Long Term Debt, Fair Value		26,225.6	[1]		24,093.9
Other Temporary Investments
Cost		289.3			355
Gross Unrealized Gains		16.3			16.4
Gross Unrealized Losses		(1.3)			(2.3)
Fair Value		304.3			369.1
Debt and Equity Securities Within Other Temporary Investments
Proceeds from Investment Sales		0		$ 0
Purchases of Investments		0.1		0.6
Gross Realized Gains on Investment Sales		0		0
Gross Realized Losses on Investment Sales		0		0
Nuclear Trust Fund Investments
Fair Value		2,684			2,474.9
Contractual Maturities, Fair Value of Debt Securities
Fair Value		2,684			2,474.9
Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		993.2			794.7
Other-Than-Temporary Impairments		(8.7)			(9.2)
Securities Activity Within Decommissioning and SNF Trusts
Proceeds from Investment Sales		111.9		508.6
Purchases of Investments		130.3		525.3
Gross Realized Gains on Investment Sales		12.3		12
Gross Realized Losses on Investment Sales		13.8		10.9
Contractual Maturities, Fair Value of Debt Securities
Within 1 year		356.4
After 1 year through 5 years		375.4
After 5 years through 10 years		172.8
After 10 years		173.9
Fair Value Measurements (Textuals)
Adjusted Cost of Debt Securities		1,000			1,000
Adjusted Cost of Domestic Equity Securities		643			629
AEP Texas Inc. [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		3,778.3			3,881.3
Long Term Debt, Fair Value		3,973.4			3,964.6
AEP Transmission Co [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		2,823.4			2,823
Long Term Debt, Fair Value		2,949.6			2,782.4
Appalachian Power Co [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		4,444			4,062.6
Long Term Debt, Fair Value		5,040.6			4,473.3
Indiana Michigan Power Co [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		3,011.4			3,035.4
Long Term Debt, Fair Value		3,201.8			3,070.2
Nuclear Trust Fund Investments
Fair Value		2,684			2,474.9
Contractual Maturities, Fair Value of Debt Securities
Fair Value		2,684			2,474.9
Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		993.2			794.7
Other-Than-Temporary Impairments		(8.7)			(9.2)
Securities Activity Within Decommissioning and SNF Trusts
Proceeds from Investment Sales		111.9		508.6
Purchases of Investments		130.3		525.3
Gross Realized Gains on Investment Sales		12.3		12
Gross Realized Losses on Investment Sales		13.8		10.9
Contractual Maturities, Fair Value of Debt Securities
Within 1 year		356.4
After 1 year through 5 years		375.4
After 5 years through 10 years		172.8
After 10 years		173.9
Fair Value Measurements (Textuals)
Adjusted Cost of Debt Securities		1,000			1,000
Adjusted Cost of Domestic Equity Securities		643			629
Ohio Power Co [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		1,693.6			1,716.6
Long Term Debt, Fair Value		1,989.2			1,919.7
Public Service Co Of Oklahoma [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		1,386.2			1,287
Long Term Debt, Fair Value		1,503.6			1,361.9
Southwestern Electric Power Co [Member]
Book Values and Fair Values of Long - term Debt
Total Long-term Debt Outstanding		2,659.1			2,713.4
Long Term Debt, Fair Value		2,763			2,670.2
Cash [Member]
Other Temporary Investments
Cost	[2]	159.6			230.6
Gross Unrealized Gains	[2]	0			0
Gross Unrealized Losses	[2]	0			0
Fair Value	[2],[3]	159.6			230.6
Fixed Income Funds [Member]
Nuclear Trust Fund Investments
Fair Value		1,078.5			1,057.1
Contractual Maturities, Fair Value of Debt Securities
Fair Value		1,078.5			1,057.1
Fixed Income Funds [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		47.6			28.4
Other-Than-Temporary Impairments		(8.7)			(9.2)
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member]
Nuclear Trust Fund Investments
Fair Value		1,078.5			1,057.1
Contractual Maturities, Fair Value of Debt Securities
Fair Value		1,078.5			1,057.1
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		47.6			28.4
Other-Than-Temporary Impairments		(8.7)			(9.2)
Mutual Funds Fixed Income [Member]
Other Temporary Investments
Cost	[4]	107.2			106.6
Gross Unrealized Gains	[4]	0			0
Gross Unrealized Losses	[4]	(1.3)			(2.3)
Fair Value	[4]	105.9			104.3
Domestic [Member]
Nuclear Trust Fund Investments
Fair Value	[5]	1,588.1			1,395.3
Contractual Maturities, Fair Value of Debt Securities
Fair Value	[5]	1,588.1			1,395.3
Domestic [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains	[6]	945.6			766.3
Other-Than-Temporary Impairments	[6]	0			0
Unrealized Gain on Securities		955		784
Unrealized Loss on Securities		9		18
Domestic [Member] | Indiana Michigan Power Co [Member]
Nuclear Trust Fund Investments
Fair Value	[5]	1,588.1			1,395.3
Contractual Maturities, Fair Value of Debt Securities
Fair Value	[5]	1,588.1			1,395.3
Domestic [Member] | Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains	[6]	945.6			766.3
Other-Than-Temporary Impairments	[6]	0			0
Unrealized Gain on Securities		955		784
Unrealized Loss on Securities		9		$ 18
Mutual Funds Equity [Member]
Other Temporary Investments
Cost		22.5			17.8
Gross Unrealized Gains		16.3			16.4
Gross Unrealized Losses		0			0
Fair Value	[5]	38.8			34.2
Cash and Cash Equivalents [Member]
Nuclear Trust Fund Investments
Fair Value	[7]	17.4			22.5
Contractual Maturities, Fair Value of Debt Securities
Fair Value	[7]	17.4			22.5
Cash and Cash Equivalents [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		0			0
Other-Than-Temporary Impairments		0			0
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member]
Nuclear Trust Fund Investments
Fair Value	[7]	17.4			22.5
Contractual Maturities, Fair Value of Debt Securities
Fair Value	[7]	17.4			22.5
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		0			0
Other-Than-Temporary Impairments		0			0
US Government Agencies Debt Securities [Member]
Nuclear Trust Fund Investments
Fair Value		1,015.6			996.1
Contractual Maturities, Fair Value of Debt Securities
Fair Value		1,015.6			996.1
US Government Agencies Debt Securities [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		44			26.7
Other-Than-Temporary Impairments		(6.7)			(7.1)
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member]
Nuclear Trust Fund Investments
Fair Value		1,015.6			996.1
Contractual Maturities, Fair Value of Debt Securities
Fair Value		1,015.6			996.1
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		44			26.7
Other-Than-Temporary Impairments		(6.7)			(7.1)
Corporate Debt [Member]
Nuclear Trust Fund Investments
Fair Value		54.2			52.4
Contractual Maturities, Fair Value of Debt Securities
Fair Value		54.2			52.4
Corporate Debt [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		2.9			1.1
Other-Than-Temporary Impairments		(1.8)			(1.9)
Corporate Debt [Member] | Indiana Michigan Power Co [Member]
Nuclear Trust Fund Investments
Fair Value		54.2			52.4
Contractual Maturities, Fair Value of Debt Securities
Fair Value		54.2			52.4
Corporate Debt [Member] | Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		2.9			1.1
Other-Than-Temporary Impairments		(1.8)			(1.9)
State and Local Jurisdiction [Member]
Nuclear Trust Fund Investments
Fair Value		8.7			8.6
Contractual Maturities, Fair Value of Debt Securities
Fair Value		8.7			8.6
State and Local Jurisdiction [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		0.7			0.6
Other-Than-Temporary Impairments		(0.2)			(0.2)
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member]
Nuclear Trust Fund Investments
Fair Value		8.7			8.6
Contractual Maturities, Fair Value of Debt Securities
Fair Value		8.7			8.6
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member] | Spent Nuclear Fuel and Decommissioning Trusts [Member]
Nuclear Trust Fund Investments
Gross Unrealized Gains		0.7			0.6
Other-Than-Temporary Impairments		(0.2)			$ (0.2)
Fair Value, Inputs, Level 1 [Member]
Book Values and Fair Values of Long - term Debt
Long Term Debt, Fair Value		$ 828
[1]	The fair value amount includes debt related to AEP’s Equity Units issued in March 2019 and has a fair value of $828 million as of March 31, 2019
[2]	Primarily represents amounts held for the repayment of debt.
[3]	Amounts in “Other’’ column primarily represent cash deposits in bank accounts with financial institutions or third-parties.  Level 1 and Level 2 amounts primarily represent investments in money market funds.
[4]	Primarily short and intermediate maturities which may be sold and do not contain maturity dates.
[5]	Amounts represent publicly traded equity securities and equity-based mutual funds.
[6]	Amount reported as Gross Unrealized Gains includes unrealized gains of $955 million and $784 million and unrealized losses of $9 million and $18 million as of March 31, 2019 and December 31, 2018
[7]	Amounts in “Other’’ column primarily represent accrued interest receivables from financial institutions.  Level 1 amounts primarily represent investments in money market funds.

Fair Value Assets and Liabiliti

Fair Value Assets and Liabilities (Details) $ in Millions		3 Months Ended
		Mar. 31, 2019USD ($)$ / MWh		Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)$ / MWh
Assets, Fair Value Disclosure
Other Temporary Investments		$ 304.3			$ 369.1
Risk Management Assets
Risk Management Assets		344.3			416.8
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		2,684			2,474.9
Total Assets		3,332.6			3,260.8
Liabilities, Fair Value Disclosure
Risk Management Liabilities		331.3			318.4
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Beginning Balance		131.2		$ 40.3
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)	[1],[2]	(23)		97.3
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date	[1]	8.5		2
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income		(15.8)		17.9
Settlements		(54.5)		(129.8)
Transfers into Level 3	[3],[4]	0.1		2.1
Transfers out of Level 3	[4]	(1.2)		(2)
Changes in Fair Value Allocated to Regulated Jurisdictions	[5]	(7.2)		34.2
Ending Balance		38.1		62
Other [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		12.5			9.1
Risk Management Assets
Risk Management Assets		(155.5)			(291.2)
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		8.1			10.2
Total Assets		(134.9)			(271.9)
Liabilities, Fair Value Disclosure
Risk Management Liabilities		(155.8)			(277.4)
Level 1 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		291.8			360
Risk Management Assets
Risk Management Assets		2.5			3.8
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,597.4			1,407.6
Total Assets		1,891.7			1,771.4
Liabilities, Fair Value Disclosure
Risk Management Liabilities		2.7			4.2
Level 2 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		0			0
Risk Management Assets
Risk Management Assets		215.2			350.6
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,078.5			1,057.1
Total Assets		1,293.7			1,407.7
Liabilities, Fair Value Disclosure
Risk Management Liabilities		240.4			369.2
Level 3 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		0			0
Risk Management Assets
Risk Management Assets		282.1			353.6
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Total Assets		282.1			353.6
Liabilities, Fair Value Disclosure
Risk Management Liabilities		244			222.4
2019 [Member] | Level 2 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		(7)			(4)
2019 [Member] | Level 3 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		27			108
2020 - 2022 [Member] | Level 2 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts					1
2020 - 2022 [Member] | Level 3 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		42			37
2023 - 2024 [Member] | Level 2 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		2			1
2023 - 2024 [Member] | Level 3 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		23			23
2025-2032 [Member] | Level 2 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		1			1
2025-2032 [Member] | Level 3 [Member]
Fair Value Measurements 1 (Textuals)
Maturity of Net Fair Value of Risk Management Contracts		(13)			(12)
Risk Management Commodity Contracts [Member]
Risk Management Assets
Risk Management Assets	[6]	324.1	[7]		382.7	[8]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	249	[7]		242.1	[8]
Risk Management Commodity Contracts [Member] | Other [Member]
Risk Management Assets
Risk Management Assets	[6]	(155.4)	[7]		(288.5)	[8]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	(155.7)	[7]		(274.7)	[8]
Risk Management Commodity Contracts [Member] | Level 1 [Member]
Risk Management Assets
Risk Management Assets	[6]	2.5	[7]		3.8	[8]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	2.7	[7]		4.2	[8]
Risk Management Commodity Contracts [Member] | Level 2 [Member]
Risk Management Assets
Risk Management Assets	[6]	200.4	[7]		326.5	[8]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	204.8	[7]		327	[8]
Risk Management Commodity Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets	[6]	276.6	[7]		340.9	[8]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	197.2	[7]		185.6	[8]
Energy Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		256.7			257.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 229			$ 212.5
Energy Contracts [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(0.05)			(0.05)
Energy Contracts [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	165.64			176.57
Energy Contracts [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	32.60			33.07
Natural Gas Contract [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		$ 0			$ 0
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 2			$ 2.5
Natural Gas Contract [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[10]	2.27			2.18
Natural Gas Contract [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[10]	2.87			3.54
Natural Gas Contract [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[10]	2.48			2.47
FTRs [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		$ 25.4			$ 96.5
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 13			$ 7.4
FTRs [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(8.34)			(11.68)
FTRs [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	10.30			17.79
FTRs [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(0.02)			1.09
Commodity Hedges [Member]
Risk Management Assets
Risk Management Assets	[6]	$ 20.2			$ 34.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	76			58.9
Commodity Hedges [Member] | Other [Member]
Risk Management Assets
Risk Management Assets	[6]	(0.1)			(2.7)
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	(0.1)			(2.7)
Commodity Hedges [Member] | Level 1 [Member]
Risk Management Assets
Risk Management Assets	[6]	0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	0			0
Commodity Hedges [Member] | Level 2 [Member]
Risk Management Assets
Risk Management Assets	[6]	14.8			24.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	29.3			24.8
Commodity Hedges [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets	[6]	5.5			12.7
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	46.8			36.8
Fair Value Hedges [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities		6.3			17.4
Fair Value Hedges [Member] | Other [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities		0			0
Fair Value Hedges [Member] | Level 1 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities		0			0
Fair Value Hedges [Member] | Level 2 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities		6.3			17.4
Fair Value Hedges [Member] | Level 3 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities		0			0
AEP Texas Inc. [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		100.6			156.7
AEP Texas Inc. [Member] | Other [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
AEP Texas Inc. [Member] | Level 1 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		100.6			156.7
AEP Texas Inc. [Member] | Level 2 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
AEP Texas Inc. [Member] | Level 3 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
AEP Texas Inc. [Member] | Risk Management Commodity Contracts [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	0.2			0.2
AEP Texas Inc. [Member] | Risk Management Commodity Contracts [Member] | Other [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	0			(0.5)
AEP Texas Inc. [Member] | Risk Management Commodity Contracts [Member] | Level 1 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	0			0
AEP Texas Inc. [Member] | Risk Management Commodity Contracts [Member] | Level 2 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	0.2			0.7
AEP Texas Inc. [Member] | Risk Management Commodity Contracts [Member] | Level 3 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6]	0			0
Appalachian Power Co [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		18.3			25.6
Spent Nuclear Fuel and Decommissioning Trusts
Total Assets		31.5			83.7
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Beginning Balance		57.8		24.7
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)	[1],[2]	(29)		68.1
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date	[1]	0		0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income		0		0
Settlements		(17.8)		(85.4)
Transfers into Level 3	[3],[4]	0		0
Transfers out of Level 3	[4]	(0.7)		0
Changes in Fair Value Allocated to Regulated Jurisdictions	[5]	(2.9)		1.7
Ending Balance		7.4		9.1
Appalachian Power Co [Member] | Other [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
Spent Nuclear Fuel and Decommissioning Trusts
Total Assets		(27.2)			(59.4)
Appalachian Power Co [Member] | Level 1 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		18.3			25.6
Spent Nuclear Fuel and Decommissioning Trusts
Total Assets		18.5			25.7
Appalachian Power Co [Member] | Level 2 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
Spent Nuclear Fuel and Decommissioning Trusts
Total Assets		26.8			59.1
Appalachian Power Co [Member] | Level 3 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
Risk Management Assets
Risk Management Assets		13.4			58.3
Spent Nuclear Fuel and Decommissioning Trusts
Total Assets		13.4			58.3
Liabilities, Fair Value Disclosure
Risk Management Liabilities		6			0.5
Appalachian Power Co [Member] | Risk Management Commodity Contracts [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	13.2			58.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	6.3			0.6
Appalachian Power Co [Member] | Risk Management Commodity Contracts [Member] | Other [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	(27.2)			(59.4)
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	(26.9)			(58.5)
Appalachian Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 1 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	0.2			0.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.2			0.2
Appalachian Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 2 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	26.8			59.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	27			58.4
Appalachian Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	13.4			58.3
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	6			0.5
Appalachian Power Co [Member] | Energy Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		3.6			2.4
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 0.4			$ 0.5
Appalachian Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	17.40			16.82
Appalachian Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	49.25			62.65
Appalachian Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	34.91			37
Appalachian Power Co [Member] | FTRs [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		$ 9.8			$ 55.9
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 5.6			$ 0
Appalachian Power Co [Member] | FTRs [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(0.06)			0.10
Appalachian Power Co [Member] | FTRs [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	2.44			15.16
Appalachian Power Co [Member] | FTRs [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	0.61			3.27
Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		$ 2,684			$ 2,474.9
Total Assets		2,688.5			2,484.1
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Beginning Balance		8.9		7.6
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)	[1],[2]	0		3
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date	[1]	0		0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income		0		0
Settlements		(5.1)		(7.4)
Transfers into Level 3	[3],[4]	0		0
Transfers out of Level 3	[4]	(0.4)		(0.3)
Changes in Fair Value Allocated to Regulated Jurisdictions	[5]	1		0
Ending Balance		4.4		2.9
Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		8.1			10.2
Total Assets		(9.3)			(33)
Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,597.4			1,407.6
Total Assets		1,597.4			1,407.6
Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,078.5			1,057.1
Total Assets		1,095.2			1,099.2
Indiana Michigan Power Co [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		5.2			10.3
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Total Assets		5.2			10.3
Liabilities, Fair Value Disclosure
Risk Management Liabilities		0.8			1.4
Indiana Michigan Power Co [Member] | Risk Management Commodity Contracts [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	4.5			9.2
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.4			0.4
Indiana Michigan Power Co [Member] | Risk Management Commodity Contracts [Member] | Other [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	(17.4)			(43.2)
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	(17)			(42.3)
Indiana Michigan Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 1 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.1			0.1
Indiana Michigan Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 2 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	16.7			42.1
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	16.5			41.2
Indiana Michigan Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	5.2			10.3
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.8			1.4
Indiana Michigan Power Co [Member] | Energy Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		1.9			1.4
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 0.3			$ 0.9
Indiana Michigan Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	17.40			16.82
Indiana Michigan Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	49.25			62.65
Indiana Michigan Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	34.91			37
Indiana Michigan Power Co [Member] | FTRs [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		$ 3.3			$ 8.9
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 0.5			$ 0.5
Indiana Michigan Power Co [Member] | FTRs [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(0.10)			(2.11)
Indiana Michigan Power Co [Member] | FTRs [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	2.02			6.21
Indiana Michigan Power Co [Member] | FTRs [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	0.86			1.06
Ohio Power Co [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		$ 16.5			$ 27.6
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Beginning Balance		(99.4)		(132.4)
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)	[1],[2]	(0.4)		0.3
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date	[1]	0		0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income		0		0
Settlements		1.8		1.1
Transfers into Level 3	[3],[4]	0		0
Transfers out of Level 3	[4]	0		0
Changes in Fair Value Allocated to Regulated Jurisdictions	[5]	(8.1)		32.5
Ending Balance		(106.1)		(98.5)
Ohio Power Co [Member] | Other [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
Ohio Power Co [Member] | Level 1 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		16.5			27.6
Ohio Power Co [Member] | Level 2 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
Ohio Power Co [Member] | Level 3 [Member]
Assets, Fair Value Disclosure
Cash and Cash Equivalents		0			0
Ohio Power Co [Member] | Risk Management Commodity Contracts [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	106.3			99.6
Ohio Power Co [Member] | Risk Management Commodity Contracts [Member] | Other [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0			(0.6)
Ohio Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 1 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0			0
Ohio Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 2 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.2			0.8
Ohio Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 3 [Member]
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	106.1			99.4
Ohio Power Co [Member] | Energy Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 106.1			$ 99.4
Ohio Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	25.35			26.29
Ohio Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	66.99			62.74
Ohio Power Co [Member] | Energy Contracts [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	43.29			42.50
Public Service Co Of Oklahoma [Member]
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Beginning Balance		$ 9.5		6.2
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)	[1],[2]	6.8		11.4
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date	[1]	0		0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income		0		0
Settlements		(13)		(16.1)
Transfers into Level 3	[3],[4]	0		0
Transfers out of Level 3	[4]	0		0
Changes in Fair Value Allocated to Regulated Jurisdictions	[5]	1.1		1.3
Ending Balance		4.4		2.8
Public Service Co Of Oklahoma [Member] | Risk Management Commodity Contracts [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	5			$ 10.4
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.7			1
Public Service Co Of Oklahoma [Member] | Risk Management Commodity Contracts [Member] | Other [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	(0.4)			(0.4)
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	(0.4)			(0.6)
Public Service Co Of Oklahoma [Member] | Risk Management Commodity Contracts [Member] | Level 1 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0			0
Public Service Co Of Oklahoma [Member] | Risk Management Commodity Contracts [Member] | Level 2 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.1			0.3
Public Service Co Of Oklahoma [Member] | Risk Management Commodity Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	5.4			10.8
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	1			1.3
Public Service Co Of Oklahoma [Member] | FTRs [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		5.4			10.8
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 1			$ 1.3
Public Service Co Of Oklahoma [Member] | FTRs [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(8.34)			(11.68)
Public Service Co Of Oklahoma [Member] | FTRs [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	10.30			10.30
Public Service Co Of Oklahoma [Member] | FTRs [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(1.09)			(1.40)
Southwestern Electric Power Co [Member]
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Beginning Balance		$ 2.3		5.9
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)	[1],[2]	3.3		0.6
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date	[1]	0		0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income		0		0
Settlements		(7.3)		(3.9)
Transfers into Level 3	[3],[4]	0		0
Transfers out of Level 3	[4]	0		0
Changes in Fair Value Allocated to Regulated Jurisdictions	[5]	1.7		(1.7)
Ending Balance		0		$ 0.9
Southwestern Electric Power Co [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		2.3			$ 5.6
Liabilities, Fair Value Disclosure
Risk Management Liabilities		2.3			3.3
Southwestern Electric Power Co [Member] | Risk Management Commodity Contracts [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	2			4.8
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	2.1			2.6
Southwestern Electric Power Co [Member] | Risk Management Commodity Contracts [Member] | Other [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	(0.3)			(0.8)
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	(0.3)			(1.1)
Southwestern Electric Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 1 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0			0
Southwestern Electric Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 2 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	0.1			0.4
Southwestern Electric Power Co [Member] | Risk Management Commodity Contracts [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets	[6],[11]	2.3			5.6
Liabilities, Fair Value Disclosure
Risk Management Liabilities	[6],[11]	2.3			3.3
Southwestern Electric Power Co [Member] | Natural Gas Contract [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		0			0
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 2			$ 2.5
Southwestern Electric Power Co [Member] | Natural Gas Contract [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[10]	2.27			2.18
Southwestern Electric Power Co [Member] | Natural Gas Contract [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[10]	2.87			3.54
Southwestern Electric Power Co [Member] | Natural Gas Contract [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[10]	2.48			2.47
Southwestern Electric Power Co [Member] | FTRs [Member] | Level 3 [Member]
Risk Management Assets
Risk Management Assets		$ 2.3			$ 5.6
Liabilities, Fair Value Disclosure
Risk Management Liabilities		$ 0.3			$ 0.8
Southwestern Electric Power Co [Member] | FTRs [Member] | Level 3 [Member] | Low [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(8.34)			(11.68)
Southwestern Electric Power Co [Member] | FTRs [Member] | Level 3 [Member] | High [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	10.30			10.30
Southwestern Electric Power Co [Member] | FTRs [Member] | Level 3 [Member] | Weighted Average [Member]
Level 3 Quantitative Information
Fair Value Significant Unobservable Input Price Per Unit | $ / MWh	[9]	(1.09)			(1.40)
Cash [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[12],[13]	$ 159.6			$ 230.6
Cash [Member] | Other [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[12]	12.5			9.1
Cash [Member] | Level 1 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[12]	147.1			221.5
Cash [Member] | Level 2 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[12]	0			0
Cash [Member] | Level 3 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[12]	0			0
Fixed Income Funds [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,078.5			1,057.1
Fixed Income Funds [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Fixed Income Funds [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Fixed Income Funds [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,078.5			1,057.1
Fixed Income Funds [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,078.5			1,057.1
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,078.5			1,057.1
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Mutual Funds Fixed Income [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[14]	105.9			104.3
Mutual Funds Fixed Income [Member] | Other [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		0			0
Mutual Funds Fixed Income [Member] | Level 1 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		105.9			104.3
Mutual Funds Fixed Income [Member] | Level 2 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		0			0
Mutual Funds Fixed Income [Member] | Level 3 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments		0			0
Mutual Funds Equity [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[15]	38.8			34.2
Mutual Funds Equity [Member] | Other [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[15]	0			0
Mutual Funds Equity [Member] | Level 1 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[15]	38.8			34.2
Mutual Funds Equity [Member] | Level 2 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[15]	0			0
Mutual Funds Equity [Member] | Level 3 [Member]
Assets, Fair Value Disclosure
Other Temporary Investments	[15]	0			0
Cash and Cash Equivalents [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	17.4			22.5
Cash and Cash Equivalents [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	8.1			10.2
Cash and Cash Equivalents [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	9.3			12.3
Cash and Cash Equivalents [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	0			0
Cash and Cash Equivalents [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	0			0
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	17.4			22.5
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	8.1			10.2
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	9.3			12.3
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	0			0
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[16]	0			0
US Government Agencies Debt Securities [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,015.6			996.1
US Government Agencies Debt Securities [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
US Government Agencies Debt Securities [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
US Government Agencies Debt Securities [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,015.6			996.1
US Government Agencies Debt Securities [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,015.6			996.1
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		1,015.6			996.1
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Corporate Debt [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		54.2			52.4
Corporate Debt [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Corporate Debt [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Corporate Debt [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		54.2			52.4
Corporate Debt [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Corporate Debt [Member] | Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		54.2			52.4
Corporate Debt [Member] | Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Corporate Debt [Member] | Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Corporate Debt [Member] | Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		54.2			52.4
Corporate Debt [Member] | Indiana Michigan Power Co [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
State and Local Jurisdiction [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		8.7			8.6
State and Local Jurisdiction [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
State and Local Jurisdiction [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
State and Local Jurisdiction [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		8.7			8.6
State and Local Jurisdiction [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		8.7			8.6
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		8.7			8.6
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts		0			0
Domestic [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	1,588.1			1,395.3
Domestic [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	0			0
Domestic [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	1,588.1			1,395.3
Domestic [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	0			0
Domestic [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	0			0
Domestic [Member] | Indiana Michigan Power Co [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	1,588.1			1,395.3
Domestic [Member] | Indiana Michigan Power Co [Member] | Other [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	0			0
Domestic [Member] | Indiana Michigan Power Co [Member] | Level 1 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	1,588.1			1,395.3
Domestic [Member] | Indiana Michigan Power Co [Member] | Level 2 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	0			0
Domestic [Member] | Indiana Michigan Power Co [Member] | Level 3 [Member]
Spent Nuclear Fuel and Decommissioning Trusts
Spent Nuclear Fuel and Decommissioning Trusts	[15]	$ 0			$ 0
[1]	Included in revenues on the statements of income.
[2]	Represents the change in fair value between the beginning of the reporting period and the settlement of the risk management commodity contract.
[3]	Represents existing assets or liabilities that were previously categorized as Level 2.
[4]	Transfers are recognized based on their value at the beginning of the reporting period that the transfer occurred.
[5]	Relates to the net gains (losses) of those contracts that are not reflected on the statements of income.  These net gains (losses) are recorded as regulatory assets/liabilities or accounts payable.
[6]	Amounts in “Other’’ column primarily represent counterparty netting of risk management and hedging contracts and associated cash collateral under the accounting guidance for “Derivatives and Hedging.”
[7]	The March 31, 2019 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(7) million in 2019, $2 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $27 million in 2019, $42 million in periods 2020-2022, $23 million in periods 2023-2024 and $(13) million
[8]	The December 31, 2018 maturity of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), is as follows: Level 2 matures $(4) million in 2019, $1 million in periods 2020-2022, $1 million in periods 2023-2024 and $1 million in periods 2025-2032; Level 3 matures $108 million in 2019, $37 million in periods 2020-2022, $23 million in periods 2023-2024 and $(12) million
[9]	Represents market prices in dollars per MWh.
[10]	Represents market prices in dollars per MMBtu.
[11]	Substantially comprised of power contracts for the Registrant Subsidiaries.
[12]	Amounts in “Other’’ column primarily represent cash deposits in bank accounts with financial institutions or third-parties.  Level 1 and Level 2 amounts primarily represent investments in money market funds.
[13]	Primarily represents amounts held for the repayment of debt.
[14]	Primarily short and intermediate maturities which may be sold and do not contain maturity dates.
[15]	Amounts represent publicly traded equity securities and equity-based mutual funds.
[16]	Amounts in “Other’’ column primarily represent accrued interest receivables from financial institutions.  Level 1 amounts primarily represent investments in money market funds.

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	7.20%	18.30%
Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 66
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(10.80%)
AEP Texas Inc. [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	10.40%	16.30%
AEP Texas Inc. [Member] | Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 1
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(3.90%)
AEP Texas Inc. [Member] | Parent Company Loss Benefit [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(2.20%)
AEP Transmission Co [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	20.90%	20.70%
Appalachian Power Co [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	(22.00%)	18.20%
Appalachian Power Co [Member] | Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 41
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(37.90%)
Indiana Michigan Power Co [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	(2.80%)	16.20%
Indiana Michigan Power Co [Member] | Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 13
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(13.70%)
Indiana Michigan Power Co [Member] | Flow-Through Items [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(6.10%)
Ohio Power Co [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	13.40%	20.50%
Ohio Power Co [Member] | Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 9
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(6.00%)
Public Service Co Of Oklahoma [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	0.60%	16.30%
Public Service Co Of Oklahoma [Member] | Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 1
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(16.90%)
Southwestern Electric Power Co [Member]
Federal Statutory Income Tax Rate	21.00%	21.00%
Effective Income Tax Rate	2.40%	18.40%
Southwestern Electric Power Co [Member] | Amortization of Excess ADIT [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Amount	$ 3
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(11.30%)
Southwestern Electric Power Co [Member] | State Tax Expense [Member]
Effective Income Tax Rate Reconciliation, Variance Explanation, Percent	(1.30%)

Leases (Details)

Leases (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Dec. 31, 2018
Lease Rental Costs
Operating Lease, Cost		$ 64.6
Finance Lease Right-of-Use Asset Amortization		14.2
Interest Expense on Finance Leases		4.1
Total Lease Rental Costs	[1]	$ 82.9
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		5 years 5 months 4 days
Weighted Average Remaining Lease Term, Finance Leases		5 years 11 months 8 days
Weighted Average Discount Rate, Operating Leases		3.61%
Weighted Average Discount Rate, Finance Leases		6.19%
Operating Cash Flows from Operating Leases		$ 28.9
Operating Cash Flows from Finance Leases		3.8
Financing Cash Flows from Finance Leases		14.3
Non-cash Acquisitions Under Operating Leases		38.5
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		21,780.6	$ 21,699.9
Other Property, Plant and Equipment		4,202.7	4,265
Total Property, Plant and Equipment		74,151.2	73,085.2
Accumulated Amortization		18,182.6	17,986.1
Net Property, Plant and Equipment Under Finance Leases		294.2
Obligations Under Finance Leases Noncurrent		797.9	782.6
Finance Lease Liability Due Within One Year		888.1	1,190.5
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		298.9
Operating Lease Asset and Related Obligations
Operating Lease Assets		1,045.4	0
Operating Lease Assets, Noncurrent		10,838.6	9,589.8
Operating Lease Noncurrent Liability		860.2	0
Operating Lease Liability Due Within One Year		228.2	0
Total Obligations Under Operating Leases		1,088.4
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		74.1
Finance Leases, Year 2		63.6
Finance Leases, Year 3		54.9
Finance Leases, Year 4		46.2
Finance Leases, Year 5		38.8
Finance Leases, Later Years		87.4
Finance Leases, Total Future Minimum Lease Payments		365
Imputed Interest on Finance Leases		66.1
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		298.9
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		263.3
Operating Leases, Year 2		253.3
Operating Leases, Year 3		235.9
Operating Leases, Year 4		226.8
Operating Leases, Year 5		61.5
Operating Leases, Later Years		180.7
Operating Leases, Total Future Minimum Lease Payments		1,221.5
Imputed Interest on Operating Leases		133.1
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		1,088.4
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			70.8
Capital Leases, 2020			60.2
Capital Leases, 2021			51.7
Capital Leases, 2022			43.8
Capital Leases, 2023			35.5
Capital Leases, Later Years			90.2
Capital Leases, Total Future Minimum Payments Due			352.2
Estimated Interest Element on Capital Leases			63.2
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			289
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			259.6
Noncancelable Operating Leases, 2020			250.1
Noncancelable Operating Leases, 2021			232.7
Noncancelable Operating Leases, 2022			222.5
Noncancelable Operating Leases, 2023			58.3
Noncancelable Operating Leases, Later Years			165.2
Noncancelable Operating Leases Total Future Minimum Lease Payments			1,188.4
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		48.8
Rockport Lease [Member]
Future Minimum Rentals, Sale Leaseback Transactions
2019	[2]	147.8
2020	[2]	147.8
2021	[2]	147.8
2022	[2]	147.2
Total Future Minimum Lease Payments	[2]	590.6
Leases (Textuals)
Sale and Leaseback Transaction, Gain (Loss), Net		$ 37
Lease Term		33 years
Boat and Barge Leases [Member]
Leases (Textuals)
Maximum Potential Lease Payments, AEPRO Barge and Boat Leases		$ 43
Guarantor Obligations, Current Carrying Value		5
Guarantee Obligations Current Carrying Value Other Liabilities Current		1
Guarantee Obligations Current Carrying Value Other Liabilities Noncurrent		4
Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		166.3
Other Property, Plant and Equipment		277.3
Total Property, Plant and Equipment		443.6
Accumulated Amortization		149.4
Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		237.4
Finance Lease Liability Due Within One Year		61.5
AEP Texas Inc. [Member]
Lease Rental Costs
Operating Lease, Cost		3.8
Finance Lease Right-of-Use Asset Amortization		1.1
Interest Expense on Finance Leases		0.3
Total Lease Rental Costs	[1]	$ 5.2
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		7 years 3 months 18 days
Weighted Average Remaining Lease Term, Finance Leases		7 years 25 days
Weighted Average Discount Rate, Operating Leases		3.82%
Weighted Average Discount Rate, Finance Leases		4.79%
Operating Cash Flows from Operating Leases		$ 3.8
Operating Cash Flows from Finance Leases		0.3
Financing Cash Flows from Finance Leases		1.2
Non-cash Acquisitions Under Operating Leases		4.6
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		352	352.1
Other Property, Plant and Equipment		734.5	727.9
Total Property, Plant and Equipment		9,906.6	9,643
Accumulated Amortization		1,686.6	1,651.2
Net Property, Plant and Equipment Under Finance Leases		29.8
Obligations Under Finance Leases Noncurrent		105.2	104
Finance Lease Liability Due Within One Year		82.4	98.3
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		29.8
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		1,231.6	1,135.4
Operating Lease Noncurrent Liability		70.2	0
Operating Lease Liability Due Within One Year		12.2	0
Total Obligations Under Operating Leases		82.4
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		6.2
Finance Leases, Year 2		5.8
Finance Leases, Year 3		5.1
Finance Leases, Year 4		4.5
Finance Leases, Year 5		3.9
Finance Leases, Later Years		10.2
Finance Leases, Total Future Minimum Lease Payments		35.7
Imputed Interest on Finance Leases		5.9
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		29.8
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		15.2
Operating Leases, Year 2		14.4
Operating Leases, Year 3		13.5
Operating Leases, Year 4		12.5
Operating Leases, Year 5		11.1
Operating Leases, Later Years		29.4
Operating Leases, Total Future Minimum Lease Payments		96.1
Imputed Interest on Operating Leases		13.7
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		82.4
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			5.8
Capital Leases, 2020			5.3
Capital Leases, 2021			4.7
Capital Leases, 2022			4.2
Capital Leases, 2023			3.7
Capital Leases, Later Years			10.1
Capital Leases, Total Future Minimum Payments Due			33.8
Estimated Interest Element on Capital Leases			5.3
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			28.5
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			15.1
Noncancelable Operating Leases, 2020			14.1
Noncancelable Operating Leases, 2021			13.2
Noncancelable Operating Leases, 2022			12.2
Noncancelable Operating Leases, 2023			10.8
Noncancelable Operating Leases, Later Years			28.4
Noncancelable Operating Leases Total Future Minimum Lease Payments			93.8
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		10.9
AEP Texas Inc. [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		0
Other Property, Plant and Equipment		39.9
Total Property, Plant and Equipment		39.9
Accumulated Amortization		10.1
AEP Texas Inc. [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		24.9
Finance Lease Liability Due Within One Year		4.9
AEP Texas Inc. [Member] | Operating Lease Assets [Member]
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		82.4
AEP Transmission Co [Member]
Lease Rental Costs
Operating Lease, Cost		0.6
Finance Lease Right-of-Use Asset Amortization		0
Interest Expense on Finance Leases		0
Total Lease Rental Costs	[1]	$ 0.6
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		2 years 8 months 15 days
Weighted Average Remaining Lease Term, Finance Leases		1 year 29 days
Weighted Average Discount Rate, Operating Leases		3.14%
Weighted Average Discount Rate, Finance Leases		9.33%
Operating Cash Flows from Operating Leases		$ 0.7
Operating Cash Flows from Finance Leases		0
Financing Cash Flows from Finance Leases		0
Non-cash Acquisitions Under Operating Leases		0
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Other Property, Plant and Equipment		174.4	174
Total Property, Plant and Equipment		8,567.2	8,268.1
Accumulated Amortization		306.7	271.9
Net Property, Plant and Equipment Under Finance Leases		0.1
Obligations Under Finance Leases Noncurrent		17	18.4
Finance Lease Liability Due Within One Year		20.3	3.8
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		0.1
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		152.5	172.4
Operating Lease Noncurrent Liability		3.2	0
Operating Lease Liability Due Within One Year		2.6	0
Total Obligations Under Operating Leases		5.8
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		0.1
Finance Leases, Year 2		0
Finance Leases, Year 3		0
Finance Leases, Year 4		0
Finance Leases, Year 5		0
Finance Leases, Later Years		0
Finance Leases, Total Future Minimum Lease Payments		0.1
Imputed Interest on Finance Leases		0
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		0.1
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		2.7
Operating Leases, Year 2		2
Operating Leases, Year 3		0.9
Operating Leases, Year 4		0.6
Operating Leases, Year 5		0
Operating Leases, Later Years		0
Operating Leases, Total Future Minimum Lease Payments		6.2
Imputed Interest on Operating Leases		0.4
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		5.8
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			0.1
Capital Leases, 2020			0
Capital Leases, 2021			0
Capital Leases, 2022			0
Capital Leases, 2023			0
Capital Leases, Later Years			0
Capital Leases, Total Future Minimum Payments Due			0.1
Estimated Interest Element on Capital Leases			0
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			0.1
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			2.3
Noncancelable Operating Leases, 2020			1.8
Noncancelable Operating Leases, 2021			1
Noncancelable Operating Leases, 2022			0.5
Noncancelable Operating Leases, 2023			0.1
Noncancelable Operating Leases, Later Years			0
Noncancelable Operating Leases Total Future Minimum Lease Payments			5.7
AEP Transmission Co [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		0
Other Property, Plant and Equipment		0.2
Total Property, Plant and Equipment		0.2
Accumulated Amortization		0.1
AEP Transmission Co [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		0
Finance Lease Liability Due Within One Year		0.1
AEP Transmission Co [Member] | Operating Lease Assets [Member]
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		5.8
Appalachian Power Co [Member]
Lease Rental Costs
Operating Lease, Cost		4.6
Finance Lease Right-of-Use Asset Amortization		1.5
Interest Expense on Finance Leases		0.7
Total Lease Rental Costs	[1]	$ 6.8
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		6 years 4 months 2 days
Weighted Average Remaining Lease Term, Finance Leases		6 years 5 months 8 days
Weighted Average Discount Rate, Operating Leases		3.66%
Weighted Average Discount Rate, Finance Leases		8.61%
Operating Cash Flows from Operating Leases		$ 4.2
Operating Cash Flows from Finance Leases		0.7
Financing Cash Flows from Finance Leases		1.6
Non-cash Acquisitions Under Operating Leases		3.5
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		6,531.5	6,509.6
Other Property, Plant and Equipment		504.5	485.8
Total Property, Plant and Equipment		14,905.6	14,792.7
Accumulated Amortization		4,174.9	4,124.4
Net Property, Plant and Equipment Under Finance Leases		40.3
Obligations Under Finance Leases Noncurrent		58.7	58.6
Finance Lease Liability Due Within One Year		103.7	150.3
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		40.3
Operating Lease Asset and Related Obligations
Operating Lease Assets		79.1	0
Operating Lease Assets, Noncurrent		996.6	923.5
Operating Lease Noncurrent Liability		64.8	0
Operating Lease Liability Due Within One Year		15	0
Total Obligations Under Operating Leases		79.8
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		9.2
Finance Leases, Year 2		8.4
Finance Leases, Year 3		7.6
Finance Leases, Year 4		7.1
Finance Leases, Year 5		6.6
Finance Leases, Later Years		12.3
Finance Leases, Total Future Minimum Lease Payments		51.2
Imputed Interest on Finance Leases		10.9
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		40.3
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		18
Operating Leases, Year 2		16.5
Operating Leases, Year 3		14
Operating Leases, Year 4		12.8
Operating Leases, Year 5		9.7
Operating Leases, Later Years		20.5
Operating Leases, Total Future Minimum Lease Payments		91.5
Imputed Interest on Operating Leases		11.7
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		79.8
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			9
Capital Leases, 2020			8
Capital Leases, 2021			7.3
Capital Leases, 2022			6.8
Capital Leases, 2023			6.3
Capital Leases, Later Years			13.3
Capital Leases, Total Future Minimum Payments Due			50.7
Estimated Interest Element on Capital Leases			10.9
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			39.8
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			17.6
Noncancelable Operating Leases, 2020			16.5
Noncancelable Operating Leases, 2021			13.9
Noncancelable Operating Leases, 2022			12.8
Noncancelable Operating Leases, 2023			9.9
Noncancelable Operating Leases, Later Years			20.5
Noncancelable Operating Leases Total Future Minimum Lease Payments			91.2
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		8.9
Appalachian Power Co [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		38.6
Other Property, Plant and Equipment		17.4
Total Property, Plant and Equipment		56
Accumulated Amortization		15.7
Appalachian Power Co [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		34
Finance Lease Liability Due Within One Year		6.3
Indiana Michigan Power Co [Member]
Lease Rental Costs
Operating Lease, Cost		23
Finance Lease Right-of-Use Asset Amortization		1.3
Interest Expense on Finance Leases		0.8
Total Lease Rental Costs	[1]	$ 25.1
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		4 years 3 months 25 days
Weighted Average Remaining Lease Term, Finance Leases		6 years 10 months 28 days
Weighted Average Discount Rate, Operating Leases		3.45%
Weighted Average Discount Rate, Finance Leases		9.03%
Operating Cash Flows from Operating Leases		$ 5
Operating Cash Flows from Finance Leases		0.7
Financing Cash Flows from Finance Leases		1.2
Non-cash Acquisitions Under Operating Leases		2.6
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		4,895	4,887.2
Other Property, Plant and Equipment		580.1	583.8
Total Property, Plant and Equipment		9,889	9,762.8
Accumulated Amortization		3,208.4	3,151.6
Net Property, Plant and Equipment Under Finance Leases		39.2
Obligations Under Finance Leases Noncurrent		68.9	87.8
Finance Lease Liability Due Within One Year		68.2	103
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		39.2
Operating Lease Asset and Related Obligations
Operating Lease Assets		326.3	0
Operating Lease Assets, Noncurrent		3,686.1	3,181
Operating Lease Noncurrent Liability		266	0
Operating Lease Liability Due Within One Year		81.8	0
Total Obligations Under Operating Leases		347.8
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		8.4
Finance Leases, Year 2		7.5
Finance Leases, Year 3		6.9
Finance Leases, Year 4		6.3
Finance Leases, Year 5		5.9
Finance Leases, Later Years		20.9
Finance Leases, Total Future Minimum Lease Payments		55.9
Imputed Interest on Finance Leases		16.7
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		39.2
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		92.5
Operating Leases, Year 2		89.5
Operating Leases, Year 3		84.9
Operating Leases, Year 4		85.2
Operating Leases, Year 5		7
Operating Leases, Later Years		20.4
Operating Leases, Total Future Minimum Lease Payments		379.5
Imputed Interest on Operating Leases		31.7
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		347.8
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			8.2
Capital Leases, 2020			7.2
Capital Leases, 2021			6.6
Capital Leases, 2022			6.1
Capital Leases, 2023			5.7
Capital Leases, Later Years			21.7
Capital Leases, Total Future Minimum Payments Due			55.5
Estimated Interest Element on Capital Leases			16.8
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			38.7
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			92.6
Noncancelable Operating Leases, 2020			89.3
Noncancelable Operating Leases, 2021			84.8
Noncancelable Operating Leases, 2022			83.8
Noncancelable Operating Leases, 2023			6.5
Noncancelable Operating Leases, Later Years			19.5
Noncancelable Operating Leases Total Future Minimum Lease Payments			376.5
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		3.9
Indiana Michigan Power Co [Member] | Rockport Lease [Member]
Future Minimum Rentals, Sale Leaseback Transactions
2019		73.9
2020		73.9
2021		73.9
2022		73.6
Total Future Minimum Lease Payments		295.3
Leases (Textuals)
Sale and Leaseback Transaction, Gain (Loss), Net		15
Indiana Michigan Power Co [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		27
Other Property, Plant and Equipment		33.4
Total Property, Plant and Equipment		60.4
Accumulated Amortization		21.2
Indiana Michigan Power Co [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		33.7
Finance Lease Liability Due Within One Year		5.5
Ohio Power Co [Member]
Lease Rental Costs
Operating Lease, Cost		3.6
Finance Lease Right-of-Use Asset Amortization		0.7
Interest Expense on Finance Leases		0.2
Total Lease Rental Costs	[1]	$ 4.5
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		8 years 2 months 15 days
Weighted Average Remaining Lease Term, Finance Leases		6 years 1 month 28 days
Weighted Average Discount Rate, Operating Leases		3.86%
Weighted Average Discount Rate, Finance Leases		4.81%
Operating Cash Flows from Operating Leases		$ 3.6
Operating Cash Flows from Finance Leases		0.2
Financing Cash Flows from Finance Leases		0.7
Non-cash Acquisitions Under Operating Leases		15.8
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Other Property, Plant and Equipment		580	574.8
Total Property, Plant and Equipment		8,619.3	8,493.5
Accumulated Amortization		2,224.1	2,218.6
Net Property, Plant and Equipment Under Finance Leases		14.6
Obligations Under Finance Leases Noncurrent		45	43.8
Finance Lease Liability Due Within One Year		147.2	214.2
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		14.6
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		846.5	841.4
Operating Lease Noncurrent Liability		74	0
Operating Lease Liability Due Within One Year		13	0
Total Obligations Under Operating Leases		87
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		3.8
Finance Leases, Year 2		3.3
Finance Leases, Year 3		2.7
Finance Leases, Year 4		2
Finance Leases, Year 5		1.5
Finance Leases, Later Years		4
Finance Leases, Total Future Minimum Lease Payments		17.3
Imputed Interest on Finance Leases		2.7
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		14.6
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		16
Operating Leases, Year 2		14.4
Operating Leases, Year 3		12.4
Operating Leases, Year 4		11.6
Operating Leases, Year 5		10.2
Operating Leases, Later Years		38.6
Operating Leases, Total Future Minimum Lease Payments		103.2
Imputed Interest on Operating Leases		16.2
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		87
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			3.3
Capital Leases, 2020			2.7
Capital Leases, 2021			2.3
Capital Leases, 2022			1.7
Capital Leases, 2023			1.2
Capital Leases, Later Years			2.8
Capital Leases, Total Future Minimum Payments Due			14
Estimated Interest Element on Capital Leases			1.9
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			12.1
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			14.5
Noncancelable Operating Leases, 2020			13.2
Noncancelable Operating Leases, 2021			10.9
Noncancelable Operating Leases, 2022			10
Noncancelable Operating Leases, 2023			8.8
Noncancelable Operating Leases, Later Years			31.7
Noncancelable Operating Leases Total Future Minimum Lease Payments			89.1
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		8.4
Ohio Power Co [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		0
Other Property, Plant and Equipment		21.3
Total Property, Plant and Equipment		21.3
Accumulated Amortization		6.7
Ohio Power Co [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		11.4
Finance Lease Liability Due Within One Year		3.2
Ohio Power Co [Member] | Operating Lease Assets [Member]
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		86.6
Public Service Co Of Oklahoma [Member]
Lease Rental Costs
Operating Lease, Cost		1.5
Finance Lease Right-of-Use Asset Amortization		0.7
Interest Expense on Finance Leases		0.1
Total Lease Rental Costs	[1]	$ 2.3
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		7 years 1 month 9 days
Weighted Average Remaining Lease Term, Finance Leases		6 years 21 days
Weighted Average Discount Rate, Operating Leases		3.67%
Weighted Average Discount Rate, Finance Leases		4.78%
Operating Cash Flows from Operating Leases		$ 1.5
Operating Cash Flows from Finance Leases		0.1
Financing Cash Flows from Finance Leases		0.7
Non-cash Acquisitions Under Operating Leases		2.3
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		1,568.6	1,577
Other Property, Plant and Equipment		306	303.5
Total Property, Plant and Equipment		5,473.1	5,439.6
Accumulated Amortization		1,496.2	1,472.9
Net Property, Plant and Equipment Under Finance Leases		12.8
Obligations Under Finance Leases Noncurrent		34.3	32.5
Finance Lease Liability Due Within One Year		63.5	64.5
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		12.8
Operating Lease Asset and Related Obligations
Operating Lease Assets		34.8	0
Operating Lease Assets, Noncurrent		469.8	407.8
Operating Lease Noncurrent Liability		29.1	0
Operating Lease Liability Due Within One Year		5.7	0
Total Obligations Under Operating Leases		34.8
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		3.6
Finance Leases, Year 2		2.9
Finance Leases, Year 3		2.1
Finance Leases, Year 4		1.7
Finance Leases, Year 5		1.4
Finance Leases, Later Years		3.3
Finance Leases, Total Future Minimum Lease Payments		15
Imputed Interest on Finance Leases		2.2
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		12.8
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		6.8
Operating Leases, Year 2		6.4
Operating Leases, Year 3		5.4
Operating Leases, Year 4		5.1
Operating Leases, Year 5		4.6
Operating Leases, Later Years		12.1
Operating Leases, Total Future Minimum Lease Payments		40.4
Imputed Interest on Operating Leases		5.6
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		34.8
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			3.4
Capital Leases, 2020			2.6
Capital Leases, 2021			2
Capital Leases, 2022			1.6
Capital Leases, 2023			1.4
Capital Leases, Later Years			3.3
Capital Leases, Total Future Minimum Payments Due			14.3
Estimated Interest Element on Capital Leases			2
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			12.3
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			6.5
Noncancelable Operating Leases, 2020			6
Noncancelable Operating Leases, 2021			5
Noncancelable Operating Leases, 2022			4.6
Noncancelable Operating Leases, 2023			4.1
Noncancelable Operating Leases, Later Years			10.7
Noncancelable Operating Leases Total Future Minimum Lease Payments			36.9
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		4
Public Service Co Of Oklahoma [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		2.6
Other Property, Plant and Equipment		18.3
Total Property, Plant and Equipment		20.9
Accumulated Amortization		8.1
Public Service Co Of Oklahoma [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		9.8
Finance Lease Liability Due Within One Year		3
Southwestern Electric Power Co [Member]
Lease Rental Costs
Operating Lease, Cost		1.8
Finance Lease Right-of-Use Asset Amortization		2.7
Interest Expense on Finance Leases		0.8
Total Lease Rental Costs	[1]	$ 5.3
Supplemental Information Related to Leases
Weighted-Average Remaining Lease Term, Operating Leases		6 years 8 months 1 day
Weighted Average Remaining Lease Term, Finance Leases		5 years 7 months 6 days
Weighted Average Discount Rate, Operating Leases		3.89%
Weighted Average Discount Rate, Finance Leases		5.04%
Operating Cash Flows from Operating Leases		$ 1.4
Operating Cash Flows from Finance Leases		0.7
Financing Cash Flows from Finance Leases		2.7
Non-cash Acquisitions Under Operating Leases		2.6
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		4,711.6	4,672.6
Other Property, Plant and Equipment		658.9	762.7
Total Property, Plant and Equipment		9,676	9,680.1
Accumulated Amortization		2,760.6	2,808.3
Net Property, Plant and Equipment Under Finance Leases		59
Obligations Under Finance Leases Noncurrent		60	51.4
Finance Lease Liability Due Within One Year		87	107.3
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		59.9
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		420.4	342
Operating Lease Noncurrent Liability		32.3	0
Operating Lease Liability Due Within One Year		6.1	0
Total Obligations Under Operating Leases		38.4
Finance Lease Liabilities Rolling Future Minimum Lease Payments
Finance Leases, Year 1		13.2
Finance Leases, Year 2		11.3
Finance Leases, Year 3		10.5
Finance Leases, Year 4		9.3
Finance Leases, Year 5		9.3
Finance Leases, Later Years		15.7
Finance Leases, Total Future Minimum Lease Payments		69.3
Imputed Interest on Finance Leases		9.4
Estimated Present Value of Future Minimum Lease Payments on Finance Leases		59.9
Operating Lease Liabilities Rolling Future Minimum Lease Payments
Operating Leases, Year 1		7.6
Operating Leases, Year 2		7.4
Operating Leases, Year 3		6.9
Operating Leases, Year 4		6.4
Operating Leases, Year 5		5.2
Operating Leases, Later Years		11.1
Operating Leases, Total Future Minimum Lease Payments		44.6
Imputed Interest on Operating Leases		6.2
Estimated Present Value of Future Minimum Lease Payments on Operating Leases		38.4
Finance Lease Future Minimum Lease Payments
Capital Leases, 2019			13.1
Capital Leases, 2020			11.5
Capital Leases, 2021			10.5
Capital Leases, 2022			9.4
Capital Leases, 2023			8.6
Capital Leases, Later Years			18.7
Capital Leases, Total Future Minimum Payments Due			71.8
Estimated Interest Element on Capital Leases			11
Estimated Present Value of Future Minimum Lease Payments on Capital Leases			60.8
Operating Lease Future Minimum Lease Payments
Noncancelable Operating Leases, 2019			7.4
Noncancelable Operating Leases, 2020			7.2
Noncancelable Operating Leases, 2021			6.7
Noncancelable Operating Leases, 2022			6.1
Noncancelable Operating Leases, 2023			5
Noncancelable Operating Leases, Later Years			11.7
Noncancelable Operating Leases Total Future Minimum Lease Payments			$ 44.1
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements		4.4
Southwestern Electric Power Co [Member] | Finance Lease Assets [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Generation		69.4
Other Property, Plant and Equipment		11.7
Total Property, Plant and Equipment		81.1
Accumulated Amortization		22.1
Southwestern Electric Power Co [Member] | Finance Lease Liabilities [Member]
Property, Plant and Equipment and Other Related Obligations Under Finance Leases
Obligations Under Finance Leases Noncurrent		49.3
Finance Lease Liability Due Within One Year		10.6
Southwestern Electric Power Co [Member] | Operating Lease Assets [Member]
Operating Lease Asset and Related Obligations
Operating Lease Assets, Noncurrent		$ 38
[1]	Excludes variable and short-term lease costs, which were immaterial for the three months ended March 31, 2019.
[2]	AEP’s future minimum lease payments include equal shares from AEGCo and I&M.

Financing Activities (Details)

Financing Activities (Details) - USD ($)		1 Months Ended	3 Months Ended
		Apr. 25, 2019	Mar. 31, 2019		Mar. 31, 2018		Dec. 31, 2018
Long-term Debt
Senior Unsecured Notes			$ 19,411,600,000				$ 18,903,300,000
Pollution Control Bonds			1,590,000,000				1,643,800,000
Notes Payable			177,000,000				204,700,000
Securitization Bonds			973,000,000				1,111,400,000
Spent Nuclear Fuel Obligation	[1]		275,300,000				273,600,000
Junior Subordinated Notes	[2]		785,000,000				0
Other Long-term Debt			1,214,800,000				1,209,900,000
Total Long-term Debt Outstanding			24,426,700,000				23,346,700,000
Long-term Debt Due Within One Year			1,528,500,000				1,698,500,000
Long-term Debt			22,898,200,000				21,648,200,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Issuances	[3]		1,311,300,000
Retirements and Principal Payments			220,600,000		$ 544,000,000
Short-term Debt:
Securitized Debt for Receivables	[4]		750,000,000				750,000,000
Commercial Paper			1,108,000,000				1,160,000,000
Total Short-term Debt			$ 1,858,000,000				$ 1,910,000,000
Securitized Debt for Receivables	[4],[5]		2.71%				2.16%
Comparative Accounts Receivable Information
Effective Interest Rates on Securitization of Accounts Receivable			2.71%		1.74%
Net Uncollectible Accounts Receivable Written Off			$ 6,400,000		$ 4,200,000
Customer Accounts Receivable Managed Portfolio
Accounts Receivable Retained Interest and Pledged as Collateral Less Uncollectible Accounts			941,400,000				$ 972,500,000
Total Principal Outstanding			750,000,000				750,000,000
Delinquent Securitized Accounts Receivable			52,700,000				50,300,000
Bad Debt Reserves Related to Securitization of Accounts Receivable			29,100,000				27,500,000
Unbilled Receivables Related to Securitization of Accounts Receivable			230,300,000				281,400,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			4,056,800,000		4,048,300,000
Financing Activities (Textuals)
Trust Fund Assets One Time Fee Obligation for Nuclear Fuel Disposition			318,000,000				317,000,000
Reacquired Pollution Controls Bonds Held by Trustees			$ 574,000,000
Equity Units Issued			16,100,000
Per unit conversion for equity units			$ 50
Net Equity Units Proceeds			785,000,000
Principal Amounts Of Junior Subordinated Debt			$ 1,000
Equity Units Annual Distribution Rate			6.125%
Forward Equity Contract Payment Rate			2.725%
Stockholders' Equity, Other			$ (55,600,000)		16,900,000
Maximum Shares Issued Under Equity Units			9,701,860
Maximum Percentage Debt to Capitalization			67.50%
Total Commitment from Bank Conduits to Finance Receivables			$ 750,000,000
Junior Subordinated Notes [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Issuances	[3],[6]		$ 805,000,000
Debt Instrument, Interest Rate, Stated Percentage	[6]		3.40%
Due Date	[6]		2024
AEP Texas Inc. [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 3,778,300,000				3,881,300,000
Long-term Debt Due Within One Year			508,600,000				501,100,000
Long-term Debt			3,269,700,000				3,380,200,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			103,500,000		96,500,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			$ 351,800,000		$ 354,100,000
Financing Activities (Textuals)
Maximum Percentage Debt to Capitalization			67.50%
AEP Texas Inc. [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 379,900,000
Maximum Loans to Money Pool			0
Average Borrowings from Money Pool			301,900,000
Average Loans to Money Pool			0
Net Loans (Borrowings) to/from Utility Money Pool			(271,200,000)
Authorized Short Term Borrowing Limit			$ 500,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.86%		2.07%
Average Interest Rate For Funds Loaned			0.00%		1.90%
AEP Texas Inc. [Member] | Nonutility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Loans to Money Pool			$ 8,000,000
Average Loans to Money Pool			7,700,000
Net Loans (Borrowings) to/from Utility Money Pool			$ 7,700,000
Maximum and Minimum Interest Rates
Maximum Interest Rate For Funds Loaned			3.02%		2.42%
Minimum Interest Rate for Funds Loaned			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Loaned			2.87%		2.00%
AEP Texas Inc. [Member] | Securitization Bonds [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 103,500,000
Debt Instrument, Interest Rate, Stated Percentage			5.31%
Due Date			2020
AEP Transmission Co [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 2,823,400,000				2,823,000,000
Long-term Debt Due Within One Year			85,000,000				85,000,000
Long-term Debt			2,738,400,000				2,738,000,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			245,200,000		$ 187,000,000	[7]
Financing Activities (Textuals)
Sub-Limit of Secured Debt			$ 50,000,000
Maximum Percentage of Consolidated Tangible Net Assets			10.00%
Tangible Capital to Tangible Assets			3.00%
Maximum Percentage Debt to Capitalization			67.50%
AEP Transmission Co [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 279,000,000
Maximum Loans to Money Pool			80,000,000
Average Borrowings from Money Pool			165,300,000
Average Loans to Money Pool			32,200,000
Net Loans (Borrowings) to/from Utility Money Pool			(191,100,000)
Authorized Short Term Borrowing Limit	[8]		$ 795,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.83%		2.06%
Average Interest Rate For Funds Loaned			2.90%		1.92%
AEP Transmission Co [Member] | Direct Borrowing [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 1,300,000
Maximum Loans to Money Pool			117,600,000
Average Borrowings from Money Pool			1,200,000
Average Loans to Money Pool			61,800,000
Borrowings from Parent			1,200,000
Loans to Parent			42,700,000
Authorized Short Term Borrowing Limit	[9]		$ 75,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate for Funds Borrowed			3.02%		2.42%
Minimum Interest Rate For Funds Borrowed			2.73%		1.83%
Maximum Interest Rate For Funds Loaned			3.02%		2.42%
Minimum Interest Rate for Funds Loaned			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.87%		2.00%
Average Interest Rate For Funds Loaned			2.86%		2.02%
Appalachian Power Co [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 4,444,000,000				4,062,600,000
Long-term Debt Due Within One Year			345,000,000				430,700,000
Long-term Debt			4,099,000,000				3,631,900,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			12,000,000		$ 11,700,000
Accounts Receivable and Accrued Unbilled Revenues
Accounts Receivable and Accrued Unbilled Revenues			132,400,000				133,300,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			788,400,000		826,300,000
Proceeds from Sale of Receivables
Proceeds from Sale of Receivables to AEP Credit			$ 374,400,000		$ 400,200,000
Financing Activities (Textuals)
Maximum Percentage Debt to Capitalization			67.50%
Appalachian Power Co [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 225,400,000
Maximum Loans to Money Pool			232,200,000
Average Borrowings from Money Pool			189,300,000
Average Loans to Money Pool			75,900,000
Net Loans (Borrowings) to/from Utility Money Pool			216,600,000
Authorized Short Term Borrowing Limit			$ 600,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.92%		2.00%
Average Interest Rate For Funds Loaned			2.79%		2.00%
Appalachian Power Co [Member] | Securitization Bonds [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 12,000,000
Debt Instrument, Interest Rate, Stated Percentage			2.01%
Due Date			2023
Appalachian Power Co [Member] | Senior Unsecured Notes [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Issuances	[3]		$ 400,000,000
Debt Instrument, Interest Rate, Stated Percentage			4.50%
Due Date			2049
Indiana Michigan Power Co [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 3,011,400,000				3,035,400,000
Long-term Debt Due Within One Year			140,400,000				155,400,000
Long-term Debt			2,871,000,000				2,880,000,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			26,500,000		$ 29,400,000
Accounts Receivable and Accrued Unbilled Revenues
Accounts Receivable and Accrued Unbilled Revenues			165,400,000				152,900,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			619,100,000		576,300,000
Proceeds from Sale of Receivables
Proceeds from Sale of Receivables to AEP Credit			$ 478,600,000		$ 459,100,000
Financing Activities (Textuals)
Maximum Percentage Debt to Capitalization			67.50%
Indiana Michigan Power Co [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 46,300,000
Maximum Loans to Money Pool			66,000,000
Average Borrowings from Money Pool			19,000,000
Average Loans to Money Pool			23,200,000
Net Loans (Borrowings) to/from Utility Money Pool			(21,900,000)
Authorized Short Term Borrowing Limit			$ 500,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.80%		2.02%
Average Interest Rate For Funds Loaned			2.87%		2.00%
Indiana Michigan Power Co [Member] | Notes Payable [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 1,400,000
Interest Rate (Variable)			Variable
Due Date			2019
Indiana Michigan Power Co [Member] | Notes Payable [Member] | Subsequent Event [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments		$ 2,000,000
Indiana Michigan Power Co [Member] | Notes Payable Two [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 1,400,000
Interest Rate (Variable)			Variable
Due Date			2019
Indiana Michigan Power Co [Member] | Notes Payable Three [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 7,100,000
Interest Rate (Variable)			Variable
Due Date			2020
Indiana Michigan Power Co [Member] | Notes Payable Four [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 5,900,000
Interest Rate (Variable)			Variable
Due Date			2021
Indiana Michigan Power Co [Member] | Notes Payable Five [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 5,000,000
Interest Rate (Variable)			Variable
Due Date			2022
Indiana Michigan Power Co [Member] | Notes Payable, Six [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 5,300,000
Interest Rate (Variable)			Variable
Due Date			2022
Indiana Michigan Power Co [Member] | Other Long Term Debt [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 400,000
Debt Instrument, Interest Rate, Stated Percentage			6.00%
Due Date			2025
Ohio Power Co [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 1,693,600,000				1,716,600,000
Long-term Debt Due Within One Year			24,600,000				47,900,000
Long-term Debt			1,669,000,000				1,668,700,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			23,400,000		$ 22,900,000
Accounts Receivable and Accrued Unbilled Revenues
Accounts Receivable and Accrued Unbilled Revenues			383,800,000				395,200,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			828,100,000		780,700,000
Proceeds from Sale of Receivables
Proceeds from Sale of Receivables to AEP Credit			636,800,000		$ 680,000,000
Financing Activities (Textuals)
Reacquired Pollution Controls Bonds Held by Trustees			345,000,000
Ohio Power Co [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			238,100,000
Maximum Loans to Money Pool			0
Average Borrowings from Money Pool			156,900,000
Average Loans to Money Pool			0
Net Loans (Borrowings) to/from Utility Money Pool			(227,600,000)
Authorized Short Term Borrowing Limit			$ 500,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.85%		2.00%
Average Interest Rate For Funds Loaned			0.00%		2.40%
Ohio Power Co [Member] | Securitization Bonds [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 23,400,000
Debt Instrument, Interest Rate, Stated Percentage			2.05%
Due Date			2019
Public Service Co Of Oklahoma [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 1,386,200,000				1,287,000,000
Long-term Debt Due Within One Year			375,500,000				375,500,000
Long-term Debt			1,010,700,000				911,500,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			100,000		$ 100,000
Accounts Receivable and Accrued Unbilled Revenues
Accounts Receivable and Accrued Unbilled Revenues			103,200,000				109,700,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			334,000,000		333,500,000
Proceeds from Sale of Receivables
Proceeds from Sale of Receivables to AEP Credit			$ 324,500,000		$ 332,600,000
Financing Activities (Textuals)
Maximum Percentage Debt to Capitalization			67.50%
Public Service Co Of Oklahoma [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 140,500,000
Maximum Loans to Money Pool			0
Average Borrowings from Money Pool			89,100,000
Average Loans to Money Pool			0
Net Loans (Borrowings) to/from Utility Money Pool			(55,200,000)
Authorized Short Term Borrowing Limit			$ 300,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.89%		2.01%
Average Interest Rate For Funds Loaned			0.00%		0.00%
Public Service Co Of Oklahoma [Member] | Other Long Term Debt [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 100,000
Debt Instrument, Interest Rate, Stated Percentage			3.00%
Due Date			2027
Public Service Co Of Oklahoma [Member] | Senior Unsecured Notes [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Issuances	[3]		$ 100,000,000
Debt Instrument, Interest Rate, Stated Percentage			3.91%
Due Date			2029
Southwestern Electric Power Co [Member]
Long-term Debt
Total Long-term Debt Outstanding			$ 2,659,100,000				2,713,400,000
Long-term Debt Due Within One Year			6,200,000				59,700,000
Long-term Debt			2,652,900,000				2,653,700,000
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			55,100,000		$ 383,400,000
Accounts Receivable and Accrued Unbilled Revenues
Accounts Receivable and Accrued Unbilled Revenues			129,100,000				$ 150,300,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			426,400,000		419,700,000
Proceeds from Sale of Receivables
Proceeds from Sale of Receivables to AEP Credit			$ 371,900,000		$ 397,600,000
Financing Activities (Textuals)
Maximum Percentage Debt to Capitalization			67.50%
Southwestern Electric Power Co [Member] | Utility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Borrowings from Money Pool			$ 100,600,000
Maximum Loans to Money Pool			81,400,000
Average Borrowings from Money Pool			41,900,000
Average Loans to Money Pool			24,000,000
Net Loans (Borrowings) to/from Utility Money Pool			(74,000,000)
Authorized Short Term Borrowing Limit			$ 350,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate			3.02%		2.42%
Minimum Interest Rate			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Borrowed			2.81%		2.10%
Average Interest Rate For Funds Loaned			2.97%		1.88%
Southwestern Electric Power Co [Member] | Nonutility [Member]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits
Maximum Loans to Money Pool			$ 2,000,000
Average Loans to Money Pool			2,000,000
Net Loans (Borrowings) to/from Utility Money Pool			$ 2,000,000
Maximum and Minimum Interest Rates
Maximum Interest Rate For Funds Loaned			3.02%		2.42%
Minimum Interest Rate for Funds Loaned			2.73%		1.83%
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool
Average Interest Rate For Funds Loaned			2.87%		2.00%
Southwestern Electric Power Co [Member] | Notes Payable [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 1,600,000
Debt Instrument, Interest Rate, Stated Percentage			4.58%
Due Date			2032
Southwestern Electric Power Co [Member] | Pollution Control Bonds [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Retirements and Principal Payments			$ 53,500,000
Debt Instrument, Interest Rate, Stated Percentage			1.60%
Due Date			2019
Transource Energy [Member] | Other Long Term Debt [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Issuances	[3]		$ 6,300,000
Interest Rate (Variable)			Variable
Due Date			2020
Transource Energy [Member] | Other Long Term Debt [Member] | Subsequent Event [Member]
Long-term Debt and Other Securities Issued, Retired and Principal Payments Made
Issuances		$ 2,000,000
Interest Rate (Variable)		Variable
Due Date		2020
Commercial Paper [Member]
Short-term Debt:
Weighted Average Interest Rate	[5]		2.75%				2.96%
July 2020 [Member]
Financing Activities (Textuals)
Commitment From Bank Conduits To Finance Receivables			$ 125,000,000
July 2021 [Member]
Financing Activities (Textuals)
Commitment From Bank Conduits To Finance Receivables			$ 625,000,000
Maximum [Member]
Financing Activities (Textuals)
AEP Share Price For Equity Unit Conversion			$ 99.58
Shares Per Equity Unit			0.6026
Minimum [Member]
Financing Activities (Textuals)
AEP Share Price For Equity Unit Conversion			$ 82.98
Shares Per Equity Unit			0.5021
Additional Paid-in Capital [Member]
Financing Activities (Textuals)
Stockholders' Equity, Other			$ 62,100,000	[10]	$ 0
Servicing Contracts [Member] | Appalachian Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			2,200,000		1,700,000
Servicing Contracts [Member] | Indiana Michigan Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			2,800,000		2,100,000
Servicing Contracts [Member] | Ohio Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			7,800,000		5,600,000
Servicing Contracts [Member] | Public Service Co Of Oklahoma [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			2,100,000		1,800,000
Servicing Contracts [Member] | Southwestern Electric Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold			$ 2,600,000		$ 1,900,000
[1]	Pursuant to the Nuclear Waste Policy Act of 1982, I&M, a nuclear licensee, has an obligation to the United States Department of Energy for SNF disposal. The obligation includes a one-time fee for nuclear fuel consumed prior to April 7, 1983. Trust fund assets related to this obligation were $318 million and $317 million as of March 31, 2019 and December 31, 2018
[2]	See “Equity Units” section below for additional information.
[3]	Amounts indicated on the statements of cash flows are net of issuance costs and premium or discount and will not tie to the issuance amounts.
[4]	Amount of securitized debt for receivables as accounted for under the “Transfers and Servicing” accounting guidance.
[5]	Weighted-average rate.
[6]	See “Equity Units” section below for additional information.
[7]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[8]	Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions.
[9]	Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions.
[10]	Includes $(62) million related to a forward equity purchase contract associated with the issuance of Equity Units. See “Equity Units” section of Footnote 13

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019		Mar. 31, 2018		Dec. 31, 2018
Disaggregation of Revenue
Revenue from Contracts with Customers		$ 4,056.8		$ 4,048.3
Total Revenues		4,056.8		4,048.3
Revenue, Performance Obligation
Fixed Performance Obligations		1,379.8
Revenue Textuals
Revenue from Related Parties		0		0
2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		732.3
2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		199.1
2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		162.7
After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		285.7
Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		3,102.8		3,070.6	[1]
Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		1,568.5		1,569.1
Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		822.1		802.1
Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		657.8		645.1
Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		54.4		54.3
Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		825.3		877.6
Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		255	[2]	359.1	[3]
Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		208.8		208.8	[4]
Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		361.5	[5]	309.7
Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		78.1	[6]	90.7	[7]
Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		4,006.2		4,038.9
Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		50.6		9.4
Alternative [Member]
Disaggregation of Revenue
Total Revenues		(0.2)	[6]	(19.1)	[7]
Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		65		48.1
Total Revenues		50.8	[6]	28.5	[7]
AEP Texas Inc. [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		351.8		354.1
Total Revenues		390.7		371.6
Revenue, Performance Obligation
Fixed Performance Obligations		278.2
Current Assets
Affiliated Companies - Contracts with Customers		15.9				$ 15
Revenue Textuals
Revenue from Related Parties		40.2		18.2
AEP Texas Inc. [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		278.2
AEP Texas Inc. [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
AEP Texas Inc. [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
AEP Texas Inc. [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
AEP Texas Inc. [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		259.1		269	[8]
AEP Texas Inc. [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		120.9		131.6
AEP Texas Inc. [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		97.9		99.4
AEP Texas Inc. [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		33		30.9
AEP Texas Inc. [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		7.3		7.1
AEP Texas Inc. [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		85.8		78
AEP Texas Inc. [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[9]	0	[10]
AEP Texas Inc. [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		85.8	[11]	78	[12]
AEP Texas Inc. [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		6.9	[13]	7.1	[14]
AEP Texas Inc. [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		38.9		17.5
AEP Texas Inc. [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(0.9)	[15]	(0.3)	[16]
AEP Texas Inc. [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0.7		1
Total Revenues		39.8	[15]	17.8	[16]
AEP Transmission Co [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		245.2		187	[17]
Total Revenues		243.5		191.7	[17],[18]
Revenue, Performance Obligation
Fixed Performance Obligations		672.5
Current Assets
Affiliated Companies - Contracts with Customers		68.8				61
Revenue Textuals
Revenue from Related Parties		193.2		160.7	[18]
AEP Transmission Co [Member] | Short-term Contract with Customer [Member]
Current Assets
Affiliated Companies - Contracts with Customers		65.9				58.6
AEP Transmission Co [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		672.5
AEP Transmission Co [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
AEP Transmission Co [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
AEP Transmission Co [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
AEP Transmission Co [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[8],[17]
AEP Transmission Co [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[17]
AEP Transmission Co [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[17]
AEP Transmission Co [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[17]
AEP Transmission Co [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[17]
AEP Transmission Co [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		242.1		185	[17]
AEP Transmission Co [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[9]	0	[10],[17]
AEP Transmission Co [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		242.1	[11]	185	[12],[17]
Revenue Textuals
Revenue from Related Parties		195		160
AEP Transmission Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		3.1	[13]	2	[14],[17]
AEP Transmission Co [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		(1.7)		4.7	[17]
AEP Transmission Co [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(1.7)	[15]	4.7	[16],[17]
AEP Transmission Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0.1	[18]
Total Revenues		0	[15]	0	[16],[17]
Appalachian Power Co [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		788.4		826.3
Total Revenues		792.8		820.4
Revenue, Performance Obligation
Fixed Performance Obligations		174.8
Current Assets
Affiliated Companies - Contracts with Customers		60.3				73.4
Revenue Textuals
Revenue from Related Parties		51.7		49.4
Appalachian Power Co [Member] | Short-term Contract with Customer [Member]
Current Assets
Affiliated Companies - Contracts with Customers		46.3				52.5
Appalachian Power Co [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		108.9
Appalachian Power Co [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		31.1
Appalachian Power Co [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		23.2
Appalachian Power Co [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		11.6
Appalachian Power Co [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		681.8		727.5	[8]
Appalachian Power Co [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		372.5		414
Appalachian Power Co [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		142.2		146.6
Appalachian Power Co [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		147.5		147.3
Appalachian Power Co [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		19.6		19.6
Appalachian Power Co [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		93.2		87.6
Appalachian Power Co [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		67.5	[9]	62.8	[10]
Revenue Textuals
Revenue from Related Parties		35		40
Appalachian Power Co [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		25.7	[11]	24.8	[12]
Appalachian Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		13.4	[13]	11.2	[14]
Appalachian Power Co [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		4.4		(5.9)
Appalachian Power Co [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		4.4	[15]	(5.9)	[16]
Appalachian Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2.4		3.5
Total Revenues		0	[15]	0	[16]
Indiana Michigan Power Co [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		619.1		576.3
Total Revenues		614.3		576.8
Revenue, Performance Obligation
Fixed Performance Obligations		43.5
Current Assets
Affiliated Companies - Contracts with Customers		55.4				75
Revenue Textuals
Revenue from Related Parties		2.3		4.7
Indiana Michigan Power Co [Member] | Short-term Contract with Customer [Member]
Current Assets
Affiliated Companies - Contracts with Customers		24				35.3
Indiana Michigan Power Co [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		21.5
Indiana Michigan Power Co [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		8.8
Indiana Michigan Power Co [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		8.8
Indiana Michigan Power Co [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		4.4
Indiana Michigan Power Co [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		479.9		432.8	[8]
Indiana Michigan Power Co [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		218.4		189
Indiana Michigan Power Co [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		121.3		109.6
Indiana Michigan Power Co [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		138.4		132
Indiana Michigan Power Co [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		1.8		2.2
Indiana Michigan Power Co [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		118.2		120.8
Indiana Michigan Power Co [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		111.9	[9]	114	[10]
Indiana Michigan Power Co [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		6.3	[11]	6.8	[12]
Indiana Michigan Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		21	[13]	22.7	[14]
Indiana Michigan Power Co [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		(4.8)		0.5
Indiana Michigan Power Co [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(4.8)	[15]	(5)	[16]
Indiana Michigan Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2		5
Total Revenues		0	[15]	5.5	[16]
Revenue Textuals
Revenue from Related Parties		15		15
Ohio Power Co [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		828.1		780.7
Total Revenues		836.8		790.9
Revenue, Performance Obligation
Fixed Performance Obligations		47.4
Current Assets
Affiliated Companies - Contracts with Customers		55.9				70.8
Revenue Textuals
Revenue from Related Parties		7.5		3.1
Ohio Power Co [Member] | Short-term Contract with Customer [Member]
Current Assets
Affiliated Companies - Contracts with Customers		31.2				46.1
Ohio Power Co [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		47.4
Ohio Power Co [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Ohio Power Co [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Ohio Power Co [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Ohio Power Co [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		775.2		722.4	[8]
Ohio Power Co [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		471.6		436.8
Ohio Power Co [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		210.5		194.5
Ohio Power Co [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		89.7		87.9
Ohio Power Co [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		3.4		3.2
Ohio Power Co [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		13.9		16
Ohio Power Co [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[9]	0	[10]
Ohio Power Co [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		13.9	[11]	16	[12]
Ohio Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		39	[13]	42.3	[14]
Ohio Power Co [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		8.7		10.2
Ohio Power Co [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		3.6	[15]	6.3	[16]
Ohio Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2.8		1.5
Total Revenues		5.1	[15]	3.9	[16]
Public Service Co Of Oklahoma [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		334		333.5
Total Revenues		332.8		336.8
Revenue, Performance Obligation
Fixed Performance Obligations		13.6
Current Assets
Affiliated Companies - Contracts with Customers		24.3				26.2
Revenue Textuals
Revenue from Related Parties		1.6		1.1
Public Service Co Of Oklahoma [Member] | Short-term Contract with Customer [Member]
Current Assets
Affiliated Companies - Contracts with Customers		13.3				12.4
Public Service Co Of Oklahoma [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		13.6
Public Service Co Of Oklahoma [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Public Service Co Of Oklahoma [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Public Service Co Of Oklahoma [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Public Service Co Of Oklahoma [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		309.8		312.8	[8]
Public Service Co Of Oklahoma [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		140		141.1
Public Service Co Of Oklahoma [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		80.8		84.3
Public Service Co Of Oklahoma [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		71		69.1
Public Service Co Of Oklahoma [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		18		18.3
Public Service Co Of Oklahoma [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		18.4		16.5
Public Service Co Of Oklahoma [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		8.6	[9]	5.9	[10]
Public Service Co Of Oklahoma [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		9.8	[11]	10.6	[12]
Public Service Co Of Oklahoma [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		5.8	[13]	4.2	[14]
Public Service Co Of Oklahoma [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		(1.2)		3.3
Public Service Co Of Oklahoma [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(1.2)	[15]	3.3	[16]
Public Service Co Of Oklahoma [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2		0.6
Total Revenues		0	[15]	0	[16]
Southwestern Electric Power Co [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		426.4		419.7
Total Revenues		421.1		419.4
Revenue, Performance Obligation
Fixed Performance Obligations		28.7
Current Assets
Affiliated Companies - Contracts with Customers		20				28.8
Revenue Textuals
Revenue from Related Parties		6.4		6.1
Southwestern Electric Power Co [Member] | Short-term Contract with Customer [Member]
Current Assets
Affiliated Companies - Contracts with Customers		10.6				$ 16.3
Southwestern Electric Power Co [Member] | 2019 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		28.7
Southwestern Electric Power Co [Member] | 2020-2021 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Southwestern Electric Power Co [Member] | 2022-2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Southwestern Electric Power Co [Member] | After 2023 [Member]
Revenue, Performance Obligation
Fixed Performance Obligations		0
Southwestern Electric Power Co [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		337.2		327.7	[8]
Southwestern Electric Power Co [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		140.1		140.1
Southwestern Electric Power Co [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		113.7		108.3
Southwestern Electric Power Co [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		81.2		77.2
Southwestern Electric Power Co [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2.2		2.1
Southwestern Electric Power Co [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		81.4		85.9
Southwestern Electric Power Co [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		57.2	[9]	59.9	[10]
Southwestern Electric Power Co [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		24.2	[11]	26	[12]
Southwestern Electric Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		7.8	[13]	6.1	[14]
Southwestern Electric Power Co [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		(5.3)		(0.3)
Southwestern Electric Power Co [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(5.3)	[15]	(0.3)	[16]
Southwestern Electric Power Co [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0.4		0.3
Total Revenues		0	[15]	0	[16]
Consolidation Eliminations [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Total Revenues		(332.2)		(256.7)
Revenue Textuals
Revenue from Related Parties		(332.2)		(256.7)
Consolidation Eliminations [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		1.8		0	[1]
Consolidation Eliminations [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Consolidation Eliminations [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Consolidation Eliminations [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		1.8		0
Consolidation Eliminations [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Consolidation Eliminations [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		(297.9)		(209.9)
Consolidation Eliminations [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		(78.5)	[2]	(30.1)	[3]
Consolidation Eliminations [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		(219.4)	[5]	(179.8)	[4]
Consolidation Eliminations [Member] | Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Consolidation Eliminations [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		(36.1)	[6]	(25.1)	[7]
Consolidation Eliminations [Member] | Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		(332.2)		(235)
Consolidation Eliminations [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		0		(21.7)
Consolidation Eliminations [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		0	[6]	0	[7]
Consolidation Eliminations [Member] | Other Revenues [Member]
Disaggregation of Revenue
Total Revenues		0	[6]	(21.7)	[7]
Consolidation Eliminations [Member] | AEP Transmission Co [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Total Revenues		0		0
Revenue Textuals
Revenue from Related Parties		0		0
Vertically Integrated Utilities [Member]
Disaggregation of Revenue
Total Revenues		2,403.3		2,408
Revenue Textuals
Revenue from Related Parties		31		26.5
Vertically Integrated Utilities [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2,069		2,079.7	[1]
Vertically Integrated Utilities [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		982.4		1,001.2
Vertically Integrated Utilities [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		511.2		508
Vertically Integrated Utilities [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		532.1		526.6
Vertically Integrated Utilities [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		43.3		43.9
Vertically Integrated Utilities [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		298.2		292
Vertically Integrated Utilities [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		224.7	[2]	217	[3]
Vertically Integrated Utilities [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		73.5	[5]	75	[4]
Vertically Integrated Utilities [Member] | Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Vertically Integrated Utilities [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		39.5	[6]	39.9	[7]
Vertically Integrated Utilities [Member] | Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2,406.7		2,411.6
Vertically Integrated Utilities [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		(3.4)		(3.6)
Vertically Integrated Utilities [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(3.4)	[6]	(9.1)	[7]
Vertically Integrated Utilities [Member] | Other Revenues [Member]
Disaggregation of Revenue
Total Revenues		0	[6]	5.5	[7]
Transmission And Distribution Companies [Member]
Disaggregation of Revenue
Total Revenues		1,222		1,162.4
Revenue Textuals
Revenue from Related Parties		42.2		21.2
Transmission And Distribution Companies [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		1,032		990.9	[1]
Transmission And Distribution Companies [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		586.1		567.9
Transmission And Distribution Companies [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		310.9		294.1
Transmission And Distribution Companies [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		123.9		118.5
Transmission And Distribution Companies [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		11.1		10.4
Transmission And Distribution Companies [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		99.6		94.1
Transmission And Distribution Companies [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[2]	0	[3]
Transmission And Distribution Companies [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		99.6	[5]	94.1	[4]
Transmission And Distribution Companies [Member] | Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Transmission And Distribution Companies [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		46	[6]	49.7	[7]
Transmission And Distribution Companies [Member] | Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		1,177.6		1,134.7
Transmission And Distribution Companies [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		44.4		27.7
Transmission And Distribution Companies [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		5	[6]	6	[7]
Transmission And Distribution Companies [Member] | Other Revenues [Member]
Disaggregation of Revenue
Total Revenues		39.4	[6]	21.7	[7]
AEP Transmission Holdco [Member]
Disaggregation of Revenue
Total Revenues		256.4		205.5
AEP Transmission Holdco [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[1]
AEP Transmission Holdco [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
AEP Transmission Holdco [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
AEP Transmission Holdco [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
AEP Transmission Holdco [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
AEP Transmission Holdco [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		255.1		219.5
AEP Transmission Holdco [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[2]	0	[3]
AEP Transmission Holdco [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		255.1	[5]	219.5	[4]
Revenue Textuals
Revenue from Related Parties		198		162
AEP Transmission Holdco [Member] | Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
AEP Transmission Holdco [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		3.1	[6]	2	[7]
AEP Transmission Holdco [Member] | Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		258.2		221.5
AEP Transmission Holdco [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		(1.8)		(16)
AEP Transmission Holdco [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		(1.8)	[6]	(16)	[7]
AEP Transmission Holdco [Member] | Other Revenues [Member]
Disaggregation of Revenue
Total Revenues		0	[6]	0	[7]
Generation And Marketing [Member]
Disaggregation of Revenue
Total Revenues		481.8		505.1
Revenue Textuals
Revenue from Related Parties		42.1		27.6
Generation And Marketing [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[1]
Generation And Marketing [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Generation And Marketing [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Generation And Marketing [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Generation And Marketing [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Generation And Marketing [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		470.3		481.9
Generation And Marketing [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		108.8	[2]	172.2	[3]
Revenue Textuals
Revenue from Related Parties		37		27
Generation And Marketing [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[5]	0	[4]
Generation And Marketing [Member] | Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		361.5		309.7
Generation And Marketing [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		2.3	[6]	2.2	[7]
Generation And Marketing [Member] | Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		472.6		484.1
Generation And Marketing [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		9.2		21
Generation And Marketing [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		0	[6]	0	[7]
Generation And Marketing [Member] | Other Revenues [Member]
Disaggregation of Revenue
Total Revenues		9.2	[6]	21	[7]
Corporate and Other [Member]
Disaggregation of Revenue
Total Revenues	[19]	25.5		24
Revenue Textuals
Revenue from Related Parties	[19]	21.7		17
Corporate and Other [Member] | Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0	[1]
Corporate and Other [Member] | Residential [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Corporate and Other [Member] | Commercial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Corporate and Other [Member] | Industrial [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Corporate and Other [Member] | Other Retail [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Corporate and Other [Member] | Wholesale and Competitive [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Corporate and Other [Member] | Wholesale Generation [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[2]	0	[3]
Corporate and Other [Member] | Wholesale Transmission [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0	[5]	0	[4]
Corporate and Other [Member] | Marketing, Competitive Retail and Renewable [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		0		0
Corporate and Other [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		23.3	[6]	22	[7]
Corporate and Other [Member] | Affiliated and Nonaffiliated [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers		23.3		22
Corporate and Other [Member] | Alternative and Other [Member]
Disaggregation of Revenue
Total Revenues		2.2		2
Corporate and Other [Member] | Alternative [Member]
Disaggregation of Revenue
Total Revenues		0	[6]	0	[7]
Corporate and Other [Member] | Other Revenues [Member]
Disaggregation of Revenue
Revenue from Contracts with Customers	[19]	3.8		7
Total Revenues		$ 2.2	[6]	$ 2	[7]
[1]	2018 amounts have been revised to reflect the reclassification of certain customer accounts between Retail classes. This reclassification did not impact previously reported Total Retail Revenues. Management concluded that these prior period disclosure only errors were immaterial individually and in the aggregate.
[2]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for Generation & Marketing was $37
[3]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for Generation & Marketing was $27
[4]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEP Transmission Holdco was $162
[5]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEP Transmission Holdco was $198
[6]	Amounts include affiliated and nonaffiliated revenues.
[7]	Amounts include affiliated and nonaffiliated revenues.
[8]	2018 amounts have been revised to reflect the reclassification of certain customer accounts between Retail classes. This reclassification did not impact previously reported Total Retail Revenues. Management concluded that these prior period disclosure only errors were immaterial individually and in the aggregate.
[9]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for APCo was $35
[10]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for APCo was $40
[11]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEPTCo was $195
[12]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for AEPTCo was $160
[13]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for I&M was $15
[14]	Amounts include affiliated and nonaffiliated revenues. The affiliated revenue for I&M was $15
[15]	Amounts include affiliated and nonaffiliated revenues.
[16]	Amounts include affiliated and nonaffiliated revenues.
[17]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[18]	The amounts presented reflect the revisions made to AEPTCo’s previously issued financial statements. See the “Revisions to Previously Issued Financial Statements” section of Note 1 for additional information.
[19]	Corporate and Other primarily includes the purchasing of receivables from certain AEP utility subsidiaries. This segment also includes Parent’s guarantee revenue received from affiliates, investment income, interest income and interest expense and other nonallocated costs.