Condensed Consolidated Statements of Changes in Equity and Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, except Share data	Appalachian Power Co [Member]	Appalachian Power Co [Member] Common Stock [Member]	Appalachian Power Co [Member] Additional Paid-in Capital [Member]	Appalachian Power Co [Member] Retained Earnings [Member]	Appalachian Power Co [Member] Accumulated Other Comprehensive Income [Member]	Columbus Southern Power Co [Member]	Columbus Southern Power Co [Member] Common Stock [Member]	Columbus Southern Power Co [Member] Additional Paid-in Capital [Member]	Columbus Southern Power Co [Member] Retained Earnings [Member]	Columbus Southern Power Co [Member] Accumulated Other Comprehensive Income [Member]	Indiana Michigan Power Co [Member]	Indiana Michigan Power Co [Member] Common Stock [Member]	Indiana Michigan Power Co [Member] Additional Paid-in Capital [Member]	Indiana Michigan Power Co [Member] Retained Earnings [Member]	Indiana Michigan Power Co [Member] Accumulated Other Comprehensive Income [Member]	Ohio Power Co [Member]	Ohio Power Co [Member] Common Stock [Member]	Ohio Power Co [Member] Additional Paid-in Capital [Member]	Ohio Power Co [Member] Retained Earnings [Member]	Ohio Power Co [Member] Accumulated Other Comprehensive Income [Member]	Public Service Co Of Oklahoma [Member]	Public Service Co Of Oklahoma [Member] Common Stock [Member]	Public Service Co Of Oklahoma [Member] Additional Paid-in Capital [Member]	Public Service Co Of Oklahoma [Member] Retained Earnings [Member]	Public Service Co Of Oklahoma [Member] Accumulated Other Comprehensive Income [Member]	Southwestern Electric Power Co [Member]	Southwestern Electric Power Co [Member] Common Stock [Member]	Southwestern Electric Power Co [Member] Additional Paid-in Capital [Member]	Southwestern Electric Power Co [Member] Retained Earnings [Member]	Southwestern Electric Power Co [Member] Accumulated Other Comprehensive Income [Member]	Southwestern Electric Power Co [Member] Noncontrolling Interests [Member]
Beginning Balance at Dec. 31, 2009	$ 2,771,577	$ 260,458	$ 1,475,393	$ 1,085,980	$ (50,254)	$ 1,359,835	$ 41,026	$ 580,663	$ 788,139	$ (49,993)	$ 1,672,783	$ 56,584	$ 981,292	$ 656,608	$ (21,701)	$ 3,234,695	$ 321,201	$ 1,123,149	$ 1,908,803	$ (118,458)	$ 811,742	$ 157,230	$ 364,231	$ 290,880	$ (599)	$ 1,524,157	$ 135,660	$ 674,979	$ 726,478	$ (12,991)	$ 31
Capital Contribution from Parent											0		0
Common Stock Dividends	(78,000)			(78,000)		(52,500)			(52,500)		(51,500)			(51,500)		(150,575)			(150,575)		(25,375)			(25,375)
Common Stock Dividends																										(1,892)					(1,892)
Preferred Stock Dividend Requirements	(450)			(399)							(170)			(170)		(366)			(366)		(103)			(103)		(114)			(114)
Gain on Reacquired Preferred Stock																					76		76
Capital Stock Expense	1		52	(51)		79		79	(79)
Subtotal - Equity	2,693,179					1,307,335					1,621,113					3,083,754					786,340					1,522,151
Other Comprehensive Income (Loss), Net of Taxes:
Cash Flow Hedges, Net of Tax	(2,542)				(2,542)	(431)				(431)	72				72	(1,255)				(1,255)	72				72	90				90
Amortization of Pension and OPEB Deferred Costs, Net of Tax	2,087				2,087	1,238				1,238	436				436	3,523				3,523						469				469
NET INCOME (LOSS)	50,663			50,663		103,766			103,766		59,660			59,660		129,451			129,451		19,628			19,628		57,788			55,364		2,424
Total Comprehensive Income	50,208					104,573					60,168					131,719					19,700					58,347
Ending Balance at Jun. 30, 2010	2,743,387	260,458	1,475,445	1,058,193	(50,709)	1,411,908	41,026	580,742	839,326	(49,186)	1,681,281	56,584	981,292	664,598	(21,193)	3,215,473	321,201	1,123,149	1,887,313	(116,190)	806,040	157,230	364,307	285,030	(527)	1,580,498	135,660	674,979	781,728	(12,432)	563
Beginning Balance at Mar. 31, 2010
Preferred Stock Dividend Requirements	(225)										(85)					(183)					(49)					(57)
Capital Stock Expense						40
Other Comprehensive Income (Loss), Net of Taxes:
NET INCOME (LOSS)	(19,619)					52,116					14,602					37,548					15,489					26,705
Ending Balance at Jun. 30, 2010	2,743,387	260,458				1,411,908	41,026				1,681,281	56,584				3,215,473	321,201	1,123,149			806,040	157,230				1,580,498	135,660	674,979
Beginning Balance at Dec. 31, 2010	2,821,679	260,458	1,475,496	1,133,748	(48,023)	1,486,215	41,026	580,812	915,713	(51,336)	1,694,349	56,584	981,294	677,360	(20,889)	3,168,424	321,201	1,123,153	1,852,889	(128,819)	842,472	157,230	364,307	312,441	8,494	1,667,349	135,660	674,979	868,840	(12,491)	361
Beginning Balance, Shares at Dec. 31, 2010																					10,482,000
Capital Contribution from Parent											0		0
Common Stock Dividends	(67,500)			(67,500)		(125,000)			(125,000)		(37,500)			(37,500)		(200,000)			(200,000)		(32,500)			(32,500)
Common Stock Dividends																										(2,126)					(2,126)
Preferred Stock Dividend Requirements	(400)			(400)							(170)			(170)		(366)			(366)		(98)			(98)		(114)			(114)
Gain on Reacquired Preferred Stock	3		3	0
Capital Stock Expense						50		50	(50)
Subtotal - Equity	2,753,782					1,361,215					1,656,679					2,968,058					809,874					1,665,109
Other Comprehensive Income (Loss), Net of Taxes:
Cash Flow Hedges, Net of Tax	1,211				1,211	492				492	1,059				1,059	29				29	(756)				(756)	255				255
Amortization of Pension and OPEB Deferred Costs, Net of Tax	1,554				1,554	1,278				1,278	473				473	4,003				4,003						1,265				1,265
NET INCOME (LOSS)	70,607			70,607		132,086			132,086		76,813			76,813		176,078			176,078		46,949			46,949		80,898			78,780		2,118
Total Comprehensive Income	73,372					133,856					78,345					180,110					46,193					82,418
Ending Balance at Jun. 30, 2011	2,827,154	260,458	1,475,499	1,136,455	(45,258)	1,495,071	41,026	580,862	922,749	(49,566)	1,735,024	56,584	981,294	716,503	(19,357)	3,148,168	321,201	1,123,153	1,828,601	(124,787)	856,067	157,230	364,307	326,792	7,738	1,747,527	135,660	674,979	947,506	(10,971)	353
Ending Balance, Shares at Jun. 30, 2011																					10,482,000
Beginning Balance at Mar. 31, 2011
Preferred Stock Dividend Requirements	(200)										(85)					(183)					(49)					(57)
Capital Stock Expense						25
Other Comprehensive Income (Loss), Net of Taxes:
NET INCOME (LOSS)	31,627					66,528					31,386					75,666					31,560					51,071
Ending Balance at Jun. 30, 2011	$ 2,827,154	$ 260,458				$ 1,495,071	$ 41,026				$ 1,735,024	$ 56,584				$ 3,148,168	$ 321,201	$ 1,123,153			$ 856,067	$ 157,230	$ 364,307			$ 1,747,527	$ 135,660	$ 674,979
Ending Balance, Shares at Jun. 30, 2011																					10,482,000