Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating Activities
Net Income (Loss)	$ 1,582,000	$ 1,446,000
Income from Discontinued Operations	18,000	16,000
Income from Continuing Operations	1,564,000	1,430,000
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	1,528,000	1,418,000
Deferred Income Taxes	529,000	385,000
Carrying Costs Income	(18,000)	(22,000)
Allowance for Equity Funds Used During Construction	(97,000)	(74,000)
Mark-to-Market of Risk Management Contracts	18,000	15,000
Amortization of Nuclear Fuel	102,000	114,000
Pension Contributions to Qualified Plan Trust	(92,000)	(70,000)
Property Taxes	247,000	220,000
Fuel Over/Under-Recovery, Net	93,000	(77,000)
Deferral of Ohio Capacity Costs, Net	35,000	(106,000)
Change in Other Noncurrent Assets	(106,000)	(41,000)
Change in Other Noncurrent Liabilities	(1,000)	271,000
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(18,000)	(19,000)
Fuel, Materials and Supplies	194,000	222,000
Accounts Payable	(13,000)	(40,000)
Accrued Taxes, Net	(68,000)	20,000
Other Current Assets	11,000	0
Other Current Liabilities	2,000	69,000
Net Cash Flows from (Used for) Operating Activities	3,910,000	3,715,000
Investing Activities
Construction Expenditures	(3,283,000)	(2,897,000)
Change in Other Temporary Investments, Net	81,000	37,000
Purchases of Investment Securities	(1,489,000)	(791,000)
Sales of Investment Securities	1,437,000	746,000
Acquisitions of Nuclear Fuel	(53,000)	(109,000)
Acquisitions of Assets/Businesses	(1,000)	(45,000)
Other Investing Activities	60,000	(20,000)
Net Cash Flows from (Used for) Investing Activities	(3,248,000)	(3,079,000)
Financing Activities
Issuance of Common Stock, Net	68,000	63,000
Issuance of Long-term Debt	2,931,000	1,206,000
Change in Short-term Debt, Net	(564,000)	525,000
Retirement of Long-term Debt	(2,131,000)	(1,536,000)
Make Whole Premium on Extinguishment of Long-term Debt	(93,000)	0
Principal Payments for Capital Lease Obligations	(74,000)	(85,000)
Dividends Paid on Common Stock	(783,000)	(736,000)
Other Financing Activities	(1,000)	3,000
Net Cash Flows from (Used for) Financing Activities	(647,000)	(560,000)
Net Increase (Decrease) in Cash and Cash Equivalents	15,000	76,000
Cash and Cash Equivalents at Beginning of Period	163,000	118,000
Cash and Cash Equivalents at End of Period	178,000	194,000
Cash Flows from Discontinued Operations
Operating Activities	10,000	10,000
Investing Activities	2,000	(2,000)
Financing Activities	(12,000)	(8,000)
Net Change in Cash and Cash Equivalents from Discontinued Operations	0	0
Cash and Cash Equivalents from Discontinued Operations - Beginning of Period	0	0
Cash and Cash Equivalents from Discontinued Operations - End of Period	0	0
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	639,000	649,000
Net Cash Paid (Received) for Income Taxes	116,000	109,000
Noncash Acquisitions Under Capital Leases	97,000	80,000
Construction Expenditures Included in Current Liabilities as of September 30,	579,000	515,000
Acquisition of Nuclear Fuel Included in Current Liabilities as of September 30,	31,000	0
Appalachian Power Co [Member]
Operating Activities
Net Income (Loss)	275,441	186,856
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	292,735	300,125
Deferred Income Taxes	179,143	114,778
Carrying Costs Income	(783)	1,130
Allowance for Equity Funds Used During Construction	(10,337)	(4,525)
Mark-to-Market of Risk Management Contracts	(5,902)	255
Pension Contributions to Qualified Plan Trust	(9,981)	(8,963)
Property Taxes	27,980	25,856
Fuel Over/Under-Recovery, Net	(1,729)	(114,022)
Change in Other Noncurrent Assets	(32,481)	(19,178)
Change in Other Noncurrent Liabilities	(27,399)	29,312
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	28,753	114,387
Fuel, Materials and Supplies	31,352	78,977
Accounts Payable	2,678	(65,358)
Accrued Taxes, Net	(75,290)	(43,092)
Other Current Assets	(2,628)	(3,748)
Other Current Liabilities	15,411	9,085
Net Cash Flows from (Used for) Operating Activities	686,963	601,875
Investing Activities
Construction Expenditures	(456,721)	(342,291)
Change in Advances to Affiliates, Net	24,984	22,395
Other Investing Activities	18,868	(1,114)
Net Cash Flows from (Used for) Investing Activities	(412,869)	(321,010)
Financing Activities
Issuance of Long-term Debt	726,330	295,039
Change in Advances from Affiliates, Net	35,224	0
Retirement of Long-term Debt	(672,552)	(512,702)
Repayments of Related Party Debt	(86,000)	0
Make Whole Premium on Extinguishment of Long-term Debt	(92,658)	0
Principal Payments for Capital Lease Obligations	(3,843)	(4,255)
Dividends Paid on Common Stock	(181,250)	(60,000)
Other Financing Activities	453	1,009
Net Cash Flows from (Used for) Financing Activities	(274,296)	(280,909)
Net Increase (Decrease) in Cash and Cash Equivalents	(202)	(44)
Cash and Cash Equivalents at Beginning of Period	2,613	2,745
Cash and Cash Equivalents at End of Period	2,411	2,701
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	128,435	136,919
Net Cash Paid (Received) for Income Taxes	33,712	22,148
Noncash Acquisitions Under Capital Leases	2,257	3,451
Construction Expenditures Included in Current Liabilities as of September 30,	80,990	54,463
Indiana Michigan Power Co [Member]
Operating Activities
Net Income (Loss)	179,907	141,049
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	150,162	150,062
Deferred Income Taxes	38,338	15,792
Amortization (Deferral) of Incremental Nuclear Refueling Outage Expenses, Net	(148)	23,951
Allowance for Equity Funds Used During Construction	(9,107)	(14,364)
Mark-to-Market of Risk Management Contracts	12,926	(2,196)
Amortization of Nuclear Fuel	101,649	114,238
Fuel Over/Under-Recovery, Net	(16,055)	18,931
Change in Other Noncurrent Assets	27,286	(36,596)
Change in Other Noncurrent Liabilities	(6,330)	66,502
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	5,467	59,646
Fuel, Materials and Supplies	29,609	14,884
Accounts Payable	(14,001)	(12,052)
Accrued Taxes, Net	4,605	30,719
Other Current Assets	6,923	11,741
Other Current Liabilities	(9,276)	(8,201)
Net Cash Flows from (Used for) Operating Activities	501,955	574,106
Investing Activities
Construction Expenditures	(337,021)	(345,369)
Change in Advances to Affiliates, Net	(27)	42,364
Purchases of Investment Securities	(1,479,149)	(789,461)
Sales of Investment Securities	1,437,336	746,272
Acquisitions of Nuclear Fuel	(53,262)	(109,224)
Other Investing Activities	9,000	11,773
Net Cash Flows from (Used for) Investing Activities	(423,123)	(443,645)
Financing Activities
Issuance of Long-term Debt	210,687	99,323
Change in Advances from Affiliates, Net	8,503	95,899
Retirement of Long-term Debt	(178,471)	(190,550)
Principal Payments for Capital Lease Obligations	(29,875)	(35,660)
Dividends Paid on Common Stock	(90,000)	(100,000)
Other Financing Activities	568	628
Net Cash Flows from (Used for) Financing Activities	(78,588)	(130,360)
Net Increase (Decrease) in Cash and Cash Equivalents	244	101
Cash and Cash Equivalents at Beginning of Period	1,020	1,317
Cash and Cash Equivalents at End of Period	1,264	1,418
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	77,450	75,789
Net Cash Paid (Received) for Income Taxes	17,203	(1,475)
Noncash Acquisitions Under Capital Leases	1,990	5,015
Construction Expenditures Included in Current Liabilities as of September 30,	51,582	69,241
Acquisition of Nuclear Fuel Included in Current Liabilities as of September 30,	31,140	11
Expected Reimbursement for Spent Nuclear Fuel Dry Cask Storage	2,136	3,208
Ohio Power Co [Member]
Operating Activities
Net Income (Loss)	184,688	171,369
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	178,609	165,152
Amortization Of Generation Deferrals	122,221	82,818
Deferred Income Taxes	28,099	27,990
Carrying Costs Income	(10,037)	(19,594)
Allowance for Equity Funds Used During Construction	(7,015)	(4,893)
Mark-to-Market of Risk Management Contracts	31,818	(5,003)
Pension Contributions to Qualified Plan Trust	(7,671)	(6,547)
Property Taxes	148,407	148,124
Fuel Over/Under-Recovery, Net	(15,674)	37,326
Deferral of Ohio Capacity Costs, Net	(30,662)	(138,737)
Change in Other Noncurrent Assets	29,168	35,962
Change in Other Noncurrent Liabilities	30,913	59,081
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	41,227	(20,395)
Fuel, Materials and Supplies	(14,969)	(1,247)
Accounts Payable	(78,831)	(83,029)
Customer Deposits	6,313	2,973
Accrued Taxes, Net	(134,699)	(173,470)
Other Current Assets	(3,233)	(947)
Other Current Liabilities	(4,707)	26,039
Net Cash Flows from (Used for) Operating Activities	493,965	302,972
Investing Activities
Construction Expenditures	(346,831)	(327,972)
Change in Restricted Cash for Securitized Funding	12,492	1,653
Change in Advances to Affiliates, Net	33,344	315,325
Proceeds from Notes Receivable Affiliated	86,000	178,580
Other Investing Activities	10,882	6,807
Net Cash Flows from (Used for) Investing Activities	(204,113)	174,393
Financing Activities
Retirement of Long-term Debt	(131,484)	(438,583)
Principal Payments for Capital Lease Obligations	(2,937)	(3,912)
Dividends Paid on Common Stock	(156,250)	(35,000)
Other Financing Activities	1,197	1,015
Net Cash Flows from (Used for) Financing Activities	(289,474)	(476,480)
Net Increase (Decrease) in Cash and Cash Equivalents	378	885
Cash and Cash Equivalents at Beginning of Period	2,870	3,004
Cash and Cash Equivalents at End of Period	3,248	3,889
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	79,019	90,188
Net Cash Paid (Received) for Income Taxes	24,060	15,523
Noncash Acquisitions Under Capital Leases	2,115	4,505
Construction Expenditures Included in Current Liabilities as of September 30,	30,209	45,691
Public Service Co Of Oklahoma [Member]
Operating Activities
Net Income (Loss)	85,522	75,983
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	90,148	73,085
Deferred Income Taxes	40,052	27,327
Allowance for Equity Funds Used During Construction	(5,952)	(2,215)
Mark-to-Market of Risk Management Contracts	(1,875)	432
Pension Contributions to Qualified Plan Trust	(5,795)	(4,439)
Property Taxes	(8,049)	(7,970)
Fuel Over/Under-Recovery, Net	76,874	(33,246)
Change in Other Noncurrent Assets	(13,066)	2,035
Change in Other Noncurrent Liabilities	7,733	(2,015)
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(2,646)	333
Fuel, Materials and Supplies	(1,067)	5,755
Accounts Payable	(9,339)	(28,643)
Accrued Taxes, Net	21,026	32,131
Other Current Assets	(1,866)	(4,034)
Other Current Liabilities	7,977	17,024
Net Cash Flows from (Used for) Operating Activities	279,677	151,543
Investing Activities
Construction Expenditures	(262,887)	(256,741)
Change in Advances to Affiliates, Net	(116,345)	0
Other Investing Activities	7,679	2,881
Net Cash Flows from (Used for) Investing Activities	(371,553)	(253,860)
Financing Activities
Issuance of Long-term Debt	248,785	74,973
Change in Advances from Affiliates, Net	(154,249)	64,095
Retirement of Long-term Debt	(319)	(34,010)
Principal Payments for Capital Lease Obligations	(2,765)	(2,785)
Other Financing Activities	735	595
Net Cash Flows from (Used for) Financing Activities	92,187	102,868
Net Increase (Decrease) in Cash and Cash Equivalents	311	551
Cash and Cash Equivalents at Beginning of Period	1,352	1,277
Cash and Cash Equivalents at End of Period	1,663	1,828
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	40,562	37,458
Net Cash Paid (Received) for Income Taxes	12,772	(416)
Noncash Acquisitions Under Capital Leases	1,546	2,098
Construction Expenditures Included in Current Liabilities as of September 30,	37,328	33,527
Southwestern Electric Power Co [Member]
Operating Activities
Net Income (Loss)	188,289	130,332
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	143,780	138,316
Deferred Income Taxes	45,672	181,482
Allowance for Equity Funds Used During Construction	(18,164)	(7,415)
Mark-to-Market of Risk Management Contracts	(272)	802
Pension Contributions to Qualified Plan Trust	(8,052)	(3,832)
Property Taxes	(13,024)	(12,503)
Fuel Over/Under-Recovery, Net	11,705	(19,547)
Change in Other Noncurrent Assets	2,756	11,926
Change in Other Noncurrent Liabilities	(1,820)	39
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	2,764	36,622
Fuel, Materials and Supplies	24,761	22,500
Accounts Payable	(17,120)	(15,046)
Accrued Taxes, Net	53,155	(76,982)
Accrued Interest	(21,231)	(24,406)
Other Current Assets	2,794	(7,448)
Other Current Liabilities	(23,678)	(2,983)
Net Cash Flows from (Used for) Operating Activities	372,315	351,857
Investing Activities
Construction Expenditures	(408,293)	(351,666)
Change in Advances to Affiliates, Net	(2,038)	0
Other Investing Activities	4,427	4,334
Net Cash Flows from (Used for) Investing Activities	(405,904)	(347,332)
Financing Activities
Issuance of Long-term Debt	445,949	99,633
Change in Advances from Affiliates, Net	0	(2,851)
Retirement of Long-term Debt	(306,750)	(3,250)
Principal Payments for Capital Lease Obligations	(13,398)	(13,673)
Dividends Paid on Common Stock	(90,000)	(75,000)
Dividends Paid on Common Stock	(3,099)	(3,483)
Other Financing Activities	789	844
Net Cash Flows from (Used for) Financing Activities	33,491	2,220
Net Increase (Decrease) in Cash and Cash Equivalents	(98)	6,745
Cash and Cash Equivalents at Beginning of Period	14,356	17,241
Cash and Cash Equivalents at End of Period	14,258	23,986
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	106,078	113,137
Net Cash Paid (Received) for Income Taxes	12,320	(13,820)
Noncash Acquisitions Under Capital Leases	1,493	3,923
Construction Expenditures Included in Current Liabilities as of September 30,	85,268	88,291
Noncash Contribution of Mutual Energy SWEPCo, LLC from Parent	(1,945)	0
Noncash Increase in Advances to Affiliates, Net due to Contribution of Mutual Energy SWEPCo, LLC	$ 1,948	$ 0