Earnings Per Share

12 Months Ended

Dec. 31, 2012

Earnings Per Share [Abstract]

Earnings Per Share

19. EARNINGS PERCOMMONSHARE (EPS)

Basic Earnings Per Share (EPS) is computed by dividing net income attributable to Duke Energy common shareholders, adjusted for distributed and undistributed earnings allocated to participating securities, by the weighted-average number of common shares outstanding during the period. Diluted EPS is computed by dividing net income attributable to Duke Energy common shareholders, as adjusted for distributed and undistributed earnings allocated to participating securities, by the diluted weighted-average number of common shares outstanding during the period. Diluted EPS reflects the potential dilution that could occur if securities or other agreements to issue common stock, such as stock options, phantom shares and stock-based performance unit awards were exercised or settled.

Duke Energy

On July 2, 2012, just prior to the close of the merger with Progress Energy, Duke Energy executed a one-for-three reverse stock split. All earnings per share amounts included in this 10-K are presented as if the one-for-three reverse stock split had been effective January 1, 2010. The following tablepresents Duke Energy's basic and diluted EPS calculations and reconciles the weighted-average number of common shares outstanding to the diluted weighted-average number of common shares outstanding

			Average
(In millions, except per-share amounts)	Income		Shares		EPS
2012
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities — basic	$	1,727		574	$	3.01
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	$	1,727		575	$	3.01
2011
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities — basic and diluted	$	1,702		444	$	3.83
2010
Income from continuing operations attributable to Duke Energy common shareholders, as adjusted for participating securities — basic	$	1,315		439	$	2.99
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		440	$	2.99

As of December 31, 2012, 2011 and 2010,1 million, 3 million and 5 million, respectively, of stock options and performance and unvested stock awards were not included in the dilutive securities calculation in the above table because either the option exercise prices were greater than the average market price of the common shares during those periods, or performance measures related to the awards had not yet been met.

Beginning in the fourth quarter of 2008, Duke Energy began issuing authorized but previously unissued shares of common stock to fulfill obligations under its Dividend Reinvestment Plan (DRIP) and other internal plans, including 401(k) plans. During the year ended December 31, 2010, Duke Energy received proceeds of $288 million from the sale of common stock associated with these plans. Proceeds from the sale of common stock associated with these plans were not significant in 2012 and 2011. Duke Energy has discontinued issuing new shares of common stock under the DRIP.

Progress Energy
	The following tables represent Progress Energy’s earnings per common share for the years ended December 31, 2011 and 2010,
respectively.
				Average
(In millions, except per-share amounts)		Income		Shares		EPS
2011
Income from continuing operations attributable to Progress Energy common shareholders, as adjusted for participating securities — basic and diluted		$	580		296	$	1.96
2010
Income from continuing operations attributable to Progress Energy common shareholders, as adjusted for participating securities — basic and diluted		$	860		291	$	2.96

As of December 31, 2010, Progress Energy had 1 million stock options outstanding which were not included in the dilutive securities calculation in the above table because either the option exercise prices were greater than the average market price of common shares during those periods, or performance measures related to the awards had not yet been met.