Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current Assets
Cash and Cash Equivalents	$ 178,000	$ 163,000
Other Temporary Investments	315,000	386,000
Fuel	376,000	581,000
Property, Plant and Equipment
Other Property, Plant and Equipment	4,036,000	5,074,000
Accumulated Depreciation and Amortization	19,588,000	19,971,000
Current Liabilities
Long-term Debt Due Within One Year	1,826,000	2,500,000
Noncurrent Liabilities
Long-term Debt	$ 17,600,000	$ 16,101,000
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	511,141,256	509,739,159
Treasury Stock, Shares	20,336,592	20,336,592
Appalachian Power Co [Member]
Current Assets
Cash and Cash Equivalents	$ 2,411	$ 2,613
Fuel	77,785	113,386
Property, Plant and Equipment
Other Property, Plant and Equipment	390,180	373,520
Accumulated Depreciation and Amortization	3,426,961	3,823,664
Current Liabilities
Long-term Debt Due Within One Year	318,020	552,212
Noncurrent Liabilities
Long-term Debt	$ 3,637,275	$ 3,342,062
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	$ 1,264	$ 1,020
Fuel	24,687	54,623
Property, Plant and Equipment
Other Property, Plant and Equipment	745,858	1,490,820
Accumulated Depreciation and Amortization	3,084,188	3,410,341
Current Liabilities
Long-term Debt Due Within One Year	301,148	382,187
Noncurrent Liabilities
Long-term Debt	$ 1,759,503	$ 1,645,210
Equity
Common Stock, No Par Value
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	$ 97,953	$ 85,657
Ohio Power Co [Member]
Current Assets
Cash and Cash Equivalents	3,248	2,870
Property, Plant and Equipment
Other Property, Plant and Equipment	446,485	390,848
Accumulated Depreciation and Amortization	2,086,931	2,038,120
Current Liabilities
Long-term Debt Due Within One Year	395,938	131,497
Noncurrent Liabilities
Long-term Debt	$ 1,770,112	$ 2,165,626
Equity
Common Stock, No Par Value
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	$ 45,864	$ 45,427
Noncurrent Liabilities
Long-term Debt	141,177	187,041
Public Service Co Of Oklahoma [Member]
Current Assets
Cash and Cash Equivalents	1,663	1,352
Fuel	15,864	16,436
Property, Plant and Equipment
Other Property, Plant and Equipment	435,807	421,568
Accumulated Depreciation and Amortization	1,383,116	1,319,554
Current Liabilities
Long-term Debt Due Within One Year	150,437	427
Noncurrent Liabilities
Long-term Debt	$ 1,140,536	$ 1,040,609
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	$ 14,258	$ 14,356
Fuel	93,125	116,955
Property, Plant and Equipment
Other Property, Plant and Equipment	895,958	878,753
Accumulated Depreciation and Amortization	2,611,129	2,503,290
Current Liabilities
Long-term Debt Due Within One Year	3,250	306,750
Noncurrent Liabilities
Long-term Debt	$ 2,280,716	$ 1,833,687
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	$ 11,693	$ 12,695
Fuel	27,194	38,920
Property, Plant and Equipment
Other Property, Plant and Equipment	291,896	288,183
Accumulated Depreciation and Amortization	153,400	142,983
AEP Subsidiaries [Member]
Current Assets
Other Temporary Investments	307,000	371,000
Current Liabilities
Long-term Debt Due Within One Year	424,000	431,000
Noncurrent Liabilities
Long-term Debt	$ 2,004,000	$ 2,260,000