Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues
Vertically Integrated Utilities	$ 2,108.2	$ 2,158.6	$ 4,326.3	$ 4,646.0
Transmission and Distribution Utilities	1,076.2	1,008.0	2,153.5	2,214.3
Generation & Marketing	655.3	627.6	1,369.2	1,486.8
Other Revenues	53.2	32.5	88.8	60.0
TOTAL REVENUES	3,892.9	3,826.7	7,937.8	8,407.1
Expenses
Fuel and Other Consumables Used for Electric Generation	680.4	755.3	1,356.0	1,826.5
Purchased Electricity for Resale	629.2	600.8	1,360.6	1,319.2
Other Operation	664.5	603.4	1,379.6	1,264.7
Maintenance	289.4	326.0	568.1	611.6
Depreciation and Amortization	513.8	497.7	1,010.9	993.1
Taxes Other Than Income Taxes	249.4	239.4	503.5	485.1
TOTAL EXPENSES	3,026.7	3,022.6	6,178.7	6,500.2
OPERATING INCOME (LOSS)	866.2	804.1	1,759.1	1,906.9
Other Income (Expense):
Interest and Investment Income	2.4	3.1	4.5	4.5
Carrying Costs Income	6.3	8.2	10.2	16.6
Allowance for Equity Funds Used During Construction	28.8	34.1	60.5	63.8
Interest Expense	(224.9)	(219.2)	(441.9)	(437.9)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	678.8	630.3	1,392.4	1,553.9
Income Tax Expense (Credit)	165.0	224.3	400.5	551.5
Equity Earnings (Loss) of Unconsolidated Subsidiaries	(7.4)	25.4	17.6	49.2
Income (Loss) from Continuing Operations	506.4	431.4	1,009.5	1,051.6
Income (Loss) from Discontinued Operations, Net of Tax	(2.5)	(0.1)	(2.5)	10.4
Net Income (Loss)	503.9	431.3	1,007.0	1,062.0
Net Income Attributable to Noncontrolling Interests	1.8	1.3	3.7	2.8
Earnings Attributable to Common Shareholders	$ 502.1	$ 430.0	$ 1,003.3	$ 1,059.2
Earnings Per Share
Weighted Average Number of Basic AEP Common Shares Outstanding	491,459,541	490,207,482	491,283,967	489,904,417
Basic Earnings Per Share Attributable to AEP Common Shareholders from Continuing Operations	$ 1.03	$ 0.88	$ 2.05	$ 2.14
Basic Earnings Per Share Attributable to AEP Common Shareholders from Discontinued Operations	(0.01)	0.00	(0.01)	0.02
Total Basic Earnings Per Share Attributable to AEP Common Shareholders	$ 1.02	$ 0.88	$ 2.04	$ 2.16
Weighted Average Number of Diluted AEP Common Shares Outstanding	491,641,400	490,484,450	491,486,853	490,212,271
Diluted Earnings Per Share Attributable to AEP Common Shareholders from Continuing Operations	$ 1.03	$ 0.88	$ 2.05	$ 2.14
Diluted Earnings Per Share Attributable to AEP Common Shareholders from Discontinued Operations	(0.01)	0.00	(0.01)	0.02
Total Diluted Earnings Per Share Attributable to AEP Common Shareholders	1.02	0.88	2.04	2.16
Common Stock, Dividends Per Share, Declared	$ 0.56	$ 0.53	$ 1.12	$ 1.06
Appalachian Power Co [Member]
Revenues
Vertically Integrated Utilities	$ 638.8	$ 645.4	$ 1,414.3	$ 1,499.6
Sales to AEP Affiliates	32.2	33.9	72.6	76.4
Other Revenues	2.5	2.7	6.6	5.0
TOTAL REVENUES	673.5	682.0	1,493.5	1,581.0
Expenses
Fuel and Other Consumables Used for Electric Generation	153.3	183.5	304.0	406.8
Purchased Electricity for Resale	63.5	65.7	171.7	178.4
Other Operation	111.2	103.7	231.8	209.8
Maintenance	60.2	57.0	129.5	109.3
Depreciation and Amortization	96.4	96.3	191.9	196.4
Taxes Other Than Income Taxes	30.6	30.1	61.9	61.1
TOTAL EXPENSES	515.2	536.3	1,090.8	1,161.8
OPERATING INCOME (LOSS)	158.3	145.7	402.7	419.2
Other Income (Expense):
Interest Income	0.2	0.5	0.5	0.9
Carrying Costs Income	1.0	0.4	0.2	0.7
Allowance for Equity Funds Used During Construction	2.3	3.9	4.6	6.9
Interest Expense	(47.3)	(48.7)	(94.3)	(99.0)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	114.5	101.8	313.7	328.7
Income Tax Expense (Credit)	41.1	42.8	114.0	127.9
Net Income (Loss)	73.4	59.0	199.7	200.8
Indiana Michigan Power Co [Member]
Revenues
Vertically Integrated Utilities	495.7	515.1	996.1	1,081.3
Sales to AEP Affiliates	7.0	6.5	18.5	7.0
Other Revenues - Affiliated	15.4	21.9	30.7	40.5
Other Revenues	4.3	0.8	9.8	1.8
TOTAL REVENUES	522.4	544.3	1,055.1	1,130.6
Expenses
Fuel and Other Consumables Used for Electric Generation	76.3	74.0	145.5	173.9
Purchased Electricity for Resale	41.0	50.3	90.6	106.2
Purchased Electricity from AEP Affiliates	56.0	60.0	101.4	115.0
Other Operation	133.7	137.3	275.0	266.3
Maintenance	48.0	59.8	88.9	107.1
Depreciation and Amortization	47.0	49.5	94.1	100.9
Taxes Other Than Income Taxes	25.6	22.0	49.0	45.4
TOTAL EXPENSES	427.6	452.9	844.5	914.8
OPERATING INCOME (LOSS)	94.8	91.4	210.6	215.8
Other Income (Expense):
Interest Income	4.2	3.5	7.4	5.3
Allowance for Equity Funds Used During Construction	4.5	3.0	6.8	7.0
Interest Expense	(27.1)	(23.0)	(49.6)	(45.8)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	76.4	74.9	175.2	182.3
Income Tax Expense (Credit)	25.1	24.3	49.2	59.0
Net Income (Loss)	51.3	50.6	126.0	123.3
Ohio Power Co [Member]
Revenues
Transmission and Distribution Utilities	728.1	670.3	1,484.8	1,544.5
Sales to AEP Affiliates	1.4	33.2	6.2	75.3
Other Revenues	1.3	2.3	3.4	4.4
TOTAL REVENUES	730.8	705.8	1,494.4	1,624.2
Expenses
Purchased Electricity for Resale	147.8	116.4	312.7	258.5
Purchased Electricity from AEP Affiliates	36.4	146.2	85.5	416.8
Amortization of Generation Deferrals	51.8	35.4	106.9	66.8
Other Operation	173.8	129.8	341.7	276.6
Maintenance	31.9	34.2	65.6	81.8
Depreciation and Amortization	58.3	55.7	119.6	114.9
Taxes Other Than Income Taxes	92.2	91.6	189.8	189.4
TOTAL EXPENSES	592.2	609.3	1,221.8	1,404.8
OPERATING INCOME (LOSS)	138.6	96.5	272.6	219.4
Other Income (Expense):
Interest Income	0.8	1.2	2.3	3.1
Carrying Costs Income	1.2	5.1	3.1	11.6
Allowance for Equity Funds Used During Construction	1.7	2.4	3.4	4.8
Interest Expense	(29.1)	(31.3)	(60.5)	(63.7)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	113.2	73.9	220.9	175.2
Income Tax Expense (Credit)	38.6	26.2	76.1	62.1
Net Income (Loss)	74.6	47.7	144.8	113.1
Public Service Co Of Oklahoma [Member]
Revenues
Vertically Integrated Utilities	298.6	317.6	570.4	622.3
Sales to AEP Affiliates	0.9	1.1	1.9	2.4
Other Revenues	0.7	0.8	2.2	1.6
TOTAL REVENUES	300.2	319.5	574.5	626.3
Expenses
Fuel and Other Consumables Used for Electric Generation	11.1	53.0	26.6	138.6
Purchased Electricity for Resale	91.2	85.1	184.5	150.6
Purchased Electricity from AEP Affiliates	0.4	0.0	0.4	0.0
Other Operation	67.9	61.0	130.8	121.8
Maintenance	24.2	25.9	46.0	47.1
Depreciation and Amortization	37.4	29.8	72.7	59.3
Taxes Other Than Income Taxes	9.0	9.2	18.7	18.5
TOTAL EXPENSES	241.2	264.0	479.7	535.9
OPERATING INCOME (LOSS)	59.0	55.5	94.8	90.4
Other Income (Expense):
Interest Income	0.1	0.0	0.3	0.1
Allowance for Equity Funds Used During Construction	1.5	2.3	3.8	3.6
Interest Expense	(15.3)	(14.8)	(29.7)	(29.4)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	45.3	43.0	69.2	64.7
Income Tax Expense (Credit)	16.4	15.9	24.6	23.9
Net Income (Loss)	28.9	27.1	44.6	40.8
Southwestern Electric Power Co [Member]
Revenues
Vertically Integrated Utilities	418.2	433.2	793.6	861.7
Sales to AEP Affiliates	8.3	4.5	11.4	7.2
Other Revenues	0.5	0.4	1.0	0.9
TOTAL REVENUES	427.0	438.1	806.0	869.8
Expenses
Fuel and Other Consumables Used for Electric Generation	122.6	125.4	244.5	283.1
Purchased Electricity for Resale	33.5	27.2	61.6	47.2
Other Operation	77.0	67.8	154.1	133.4
Maintenance	37.1	38.3	68.2	65.7
Depreciation and Amortization	49.4	47.9	96.9	94.9
Taxes Other Than Income Taxes	21.5	21.4	43.4	43.1
TOTAL EXPENSES	341.1	328.0	668.7	667.4
OPERATING INCOME (LOSS)	85.9	110.1	137.3	202.4
Other Income (Expense):
Interest Income	0.0	1.2	0.0	1.2
Allowance for Equity Funds Used During Construction	2.0	5.9	9.4	11.1
Interest Expense	(31.5)	(32.0)	(59.4)	(62.2)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	56.4	85.2	87.3	152.5
Income Tax Expense (Credit)	13.3	26.8	20.7	48.0
Equity Earnings (Loss) of Unconsolidated Subsidiaries	1.2	1.1	2.2	1.7
Net Income (Loss)	44.3	59.5	68.8	106.2
Net Income Attributable to Noncontrolling Interests	1.1	1.0	2.2	2.0
Earnings Attributable to Common Shareholders	$ 43.2	$ 58.5	$ 66.6	$ 104.2