Significant Accounting Matters (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	$ 338,000	$ 362,000	$ 701,000	$ 751,000
Weighted Average Number of Basic AEP Common Shares Outstanding	486,293,026	484,500,029	486,059,643	484,164,065
Total Basic Earnings Per Share Attributable to AEP Common Shareholders	$ 0.69	$ 0.75	$ 1.44	$ 1.55
Weighted Average Dilutive Effect of:
Weighted Average Number of Diluted AEP Common Shares Outstanding	486,763,615	484,860,690	486,555,121	484,554,779
Total Diluted Earnings Per Share Attributable to AEP Common Shareholders	$ 0.69	$ 0.75	$ 1.44	$ 1.55
Amounts Attributable to AEP Common Shareholders
Net Income	338,000	362,000	701,000	751,000
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Antidilutive Shares Outstanding			0	0
Southwestern Electric Power Co [Member]
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	29,171	53,841	39,629	89,153
Amounts Attributable to AEP Common Shareholders
Net Income	$ 29,171	$ 53,841	$ 39,629	$ 89,153
Stock Options [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares	0	100,000	0	100,000
Dilutive Securities, Effect on Basic Earnings Per Share	$ 0	$ 0	$ 0	$ 0
Restricted Stock Units [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares	500,000	300,000	500,000	300,000
Dilutive Securities, Effect on Basic Earnings Per Share	$ 0	$ 0	$ 0	$ 0