Significant Accounting Matters (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	$ 390,000	$ 338,000	$ 950,000	$ 701,000
Weighted Average Number of Basic AEP Common Shares Outstanding	488,291,576	486,293,026	488,080,505	486,059,643
Total Basic Earnings Per Share Attributable to AEP Common Shareholders	$ 0.80	$ 0.69	$ 1.95	$ 1.44
Weighted Average Dilutive Effect of:
Weighted Average Number of Diluted AEP Common Shares Outstanding	488,538,227	486,763,615	488,405,869	486,555,121
Total Diluted Earnings Per Share Attributable to AEP Common Shareholders	$ 0.80	$ 0.69	$ 1.95	$ 1.44
Amounts Attributable to AEP Common Shareholders
Net Income	390,000	338,000	950,000	701,000
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	31,697	29,171	53,557	39,629
Amounts Attributable to AEP Common Shareholders
Net Income	$ 31,697	$ 29,171	$ 53,557	$ 39,629
Restricted Stock Units [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares	200,000	500,000	300,000	500,000
Dilutive Securities, Effect on Basic Earnings Per Share	$ 0	$ 0	$ 0	$ 0