Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share [Abstract]

Schedule Of Earnings Per Share

(in millions, except per share amounts)	Income		Average     Shares		EPS
2011
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities—basic	$	1,702		1,332	$	1.28
Effect of dilutive securities:
Stock options, performance and restricted stock				1
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities—diluted	$	1,702		1,333	$	1.28
2010
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities—basic	$	1,315		1,318	$	1.00
Effect of dilutive securities:
Stock options, performance and restricted stock				1
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities—diluted	$	1,315		1,319	$	1.00
2009
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities—basic	$	1,061		1,293	$	0.82
Effect of dilutive securities:
Stock options, performance and restricted stock				1
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities—diluted	$	1,061		1,294	$	0.82