Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues
Vertically Integrated Utilities	$ 2,159,000	$ 2,236,000	$ 4,646,000	$ 4,785,000
Transmission and Distribution Utilities	1,008,000	1,064,000	2,214,000	2,225,000
Generation & Marketing	628,000	573,000	1,487,000	1,394,000
Other Revenues	147,000	171,000	303,000	288,000
TOTAL REVENUES	3,942,000	4,044,000	8,650,000	8,692,000
Expenses
Fuel and Other Consumables Used for Electric Generation	756,000	1,043,000	1,827,000	2,211,000
Purchased Electricity for Resale	601,000	473,000	1,319,000	1,111,000
Other Operation	695,000	760,000	1,441,000	1,540,000
Maintenance	333,000	340,000	627,000	632,000
Depreciation and Amortization	506,000	443,000	1,011,000	934,000
Taxes Other Than Income Taxes	242,000	218,000	492,000	456,000
TOTAL EXPENSES	3,133,000	3,277,000	6,717,000	6,884,000
OPERATING INCOME (LOSS)	809,000	767,000	1,933,000	1,808,000
Other Income (Expense):
Interest and Investment Income	3,000	3,000	4,000	4,000
Carrying Costs Income	9,000	9,000	17,000	15,000
Allowance for Equity Funds Used During Construction	34,000	25,000	64,000	47,000
Interest Expense	(224,000)	(221,000)	(447,000)	(441,000)
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	631,000	583,000	1,571,000	1,433,000
Income Tax Expense (Credit)	225,000	215,000	558,000	522,000
Equity Earnings (Loss) of Unconsolidated Subsidiaries	25,000	23,000	49,000	41,000
NET INCOME (LOSS)	431,000	391,000	1,062,000	952,000
Net Income Attributable to Noncontrolling Interests	1,000	1,000	3,000	2,000
EARNINGS ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 430,000	$ 390,000	$ 1,059,000	$ 950,000
Earnings Per Share
WEIGHTED AVERAGE NUMBER OF BASIC AEP COMMON SHARES OUTSTANDING	490,207,482	488,291,576	489,904,417	488,080,505
TOTAL BASIC EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS	$ 0.88	$ 0.80	$ 2.16	$ 1.95
WEIGHTED AVERAGE NUMBER OF DILUTED AEP COMMON SHARES OUTSTANDING	490,484,450	488,538,227	490,212,271	488,405,869
TOTAL DILUTED EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS	$ 0.88	$ 0.80	$ 2.16	$ 1.95
CASH DIVIDENDS DECLARED PER SHARE	$ 0.53	$ 0.5	$ 1.06	$ 1
Appalachian Power Co [Member]
Revenues
Vertically Integrated Utilities	$ 645,452	$ 664,051	$ 1,499,631	$ 1,530,508
Sales to AEP Affiliates	33,836	28,070	76,351	72,984
Other Revenues	2,692	2,547	5,013	4,567
TOTAL REVENUES	681,980	694,668	1,580,995	1,608,059
Expenses
Fuel and Other Consumables Used for Electric Generation	183,485	202,903	406,732	433,640
Purchased Electricity for Resale	65,715	86,033	178,384	255,024
Purchased Electricity from AEP Affiliates	0	0	0	4,662
Other Operation	103,720	99,896	209,790	193,434
Maintenance	57,037	69,484	109,334	129,574
Depreciation and Amortization	96,297	95,650	196,440	200,236
Taxes Other Than Income Taxes	30,040	30,025	61,087	60,802
TOTAL EXPENSES	536,294	583,991	1,161,767	1,277,372
OPERATING INCOME (LOSS)	145,686	110,677	419,228	330,687
Other Income (Expense):
Interest Income	449	389	838	790
Carrying Costs Income	417	263	710	(1,612)
Allowance for Equity Funds Used During Construction	3,897	1,625	6,905	2,860
Interest Expense	(48,684)	(53,130)	(98,975)	(104,802)
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	101,765	59,824	328,706	227,923
Income Tax Expense (Credit)	42,713	23,577	127,861	89,825
NET INCOME (LOSS)	59,052	36,247	200,845	138,098
Indiana Michigan Power Co [Member]
Revenues
Vertically Integrated Utilities	515,027	506,997	1,081,277	1,121,840
Sales to AEP Affiliates	6,504	1,068	6,957	3,352
Other Revenues - Affiliated	21,931	25,262	40,511	49,989
Other Revenues	812	549	1,840	549
TOTAL REVENUES	544,274	533,876	1,130,585	1,175,730
Expenses
Fuel and Other Consumables Used for Electric Generation	74,041	113,700	173,925	270,343
Purchased Electricity for Resale	50,260	27,086	106,167	32,448
Purchased Electricity from AEP Affiliates	59,993	65,190	114,958	137,246
Other Operation	137,306	146,272	266,266	287,622
Maintenance	59,829	54,246	107,180	102,811
Depreciation and Amortization	49,540	49,446	100,947	99,477
Taxes Other Than Income Taxes	21,977	20,803	45,384	42,626
TOTAL EXPENSES	452,946	476,743	914,827	972,573
OPERATING INCOME (LOSS)	91,328	57,133	215,758	203,157
Other Income (Expense):
Interest Income	3,578	1,729	5,326	2,778
Allowance for Equity Funds Used During Construction	2,907	4,804	6,950	8,768
Interest Expense	(22,968)	(23,705)	(45,745)	(49,338)
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	74,845	39,961	182,289	165,365
Income Tax Expense (Credit)	24,264	12,627	59,034	50,942
NET INCOME (LOSS)	50,581	27,334	123,255	114,423
Ohio Power Co [Member]
Revenues
Transmission and Distribution Utilities	670,250	739,962	1,544,467	1,586,868
Sales to AEP Affiliates	33,158	44,443	75,264	76,421
Other Revenues	2,346	1,756	4,463	3,064
TOTAL REVENUES	705,754	786,161	1,624,194	1,666,353
Expenses
Purchased Electricity for Resale	116,434	64,059	258,514	143,189
Purchased Electricity from AEP Affiliates	146,207	267,631	416,811	581,755
Amortization of Generation Deferrals	35,301	24,977	66,755	56,163
Other Operation	129,829	131,485	276,673	282,911
Maintenance	34,214	48,590	81,787	83,241
Depreciation and Amortization	55,640	51,485	114,852	110,184
Taxes Other Than Income Taxes	91,639	83,913	189,426	179,170
TOTAL EXPENSES	609,264	672,140	1,404,818	1,436,613
OPERATING INCOME (LOSS)	96,490	114,021	219,376	229,740
Other Income (Expense):
Interest Income	1,250	2,899	3,163	6,173
Carrying Costs Income	5,153	6,874	11,613	13,988
Allowance for Equity Funds Used During Construction	2,343	1,342	4,787	3,068
Interest Expense	(31,271)	(32,759)	(63,720)	(65,766)
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	73,965	92,377	175,219	187,203
Income Tax Expense (Credit)	26,213	35,842	62,100	69,894
NET INCOME (LOSS)	47,752	56,535	113,119	117,309
Public Service Co Of Oklahoma [Member]
Revenues
Vertically Integrated Utilities	317,611	316,524	622,284	613,234
Sales to AEP Affiliates	1,164	854	2,443	5,451
Other Revenues	729	1,437	1,549	1,515
TOTAL REVENUES	319,504	318,815	626,276	620,200
Expenses
Fuel and Other Consumables Used for Electric Generation	52,981	41,612	138,580	107,549
Purchased Electricity for Resale	85,036	104,604	150,559	184,295
Purchased Electricity from AEP Affiliates	0	0	0	11,024
Other Operation	61,028	62,785	121,793	121,496
Maintenance	25,943	29,678	47,083	54,423
Depreciation and Amortization	29,782	24,607	59,316	48,589
Taxes Other Than Income Taxes	9,238	6,651	18,516	18,620
TOTAL EXPENSES	264,008	269,937	535,847	545,996
OPERATING INCOME (LOSS)	55,496	48,878	90,429	74,204
Other Income (Expense):
Interest Income	92	4	128	1
Allowance for Equity Funds Used During Construction	2,283	590	3,610	2,021
Interest Expense	(14,852)	(13,779)	(29,422)	(27,096)
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	43,019	35,693	64,745	49,130
Income Tax Expense (Credit)	15,921	13,244	23,962	18,233
NET INCOME (LOSS)	27,098	22,449	40,783	30,897
Southwestern Electric Power Co [Member]
Revenues
Vertically Integrated Utilities	433,187	444,652	861,722	871,279
Sales to AEP Affiliates	4,486	3,947	7,156	17,545
Other Revenues	364	684	868	1,049
TOTAL REVENUES	438,037	449,283	869,746	889,873
Expenses
Fuel and Other Consumables Used for Electric Generation	125,365	161,116	283,097	306,703
Purchased Electricity for Resale	27,188	40,255	47,202	101,420
Purchased Electricity from AEP Affiliates	0	0	0	3,766
Other Operation	67,899	69,304	133,444	137,841
Maintenance	38,237	33,668	65,651	64,079
Depreciation and Amortization	47,964	45,864	94,918	91,525
Taxes Other Than Income Taxes	21,316	20,289	43,048	41,026
TOTAL EXPENSES	327,969	370,496	667,360	746,360
OPERATING INCOME (LOSS)	110,068	78,787	202,386	143,513
Other Income (Expense):
Interest Income	1,184	206	1,164	92
Allowance for Equity Funds Used During Construction	5,882	2,197	11,111	4,278
Interest Expense	(31,945)	(31,738)	(62,160)	(63,614)
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)	85,189	49,452	152,501	84,269
Income Tax Expense (Credit)	26,887	17,045	48,059	29,210
Equity Earnings (Loss) of Unconsolidated Subsidiaries	1,124	416	1,721	726
NET INCOME (LOSS)	59,426	32,823	106,163	55,785
Net Income Attributable to Noncontrolling Interests	956	1,126	1,989	2,228
EARNINGS ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 58,470	$ 31,697	$ 104,174	$ 53,557