Earnings Per Share

12 Months Ended

Dec. 31, 2011

Earnings Per Share [Abstract]

Earnings Per Share

EARNINGS PER SHARE

Basic earnings per share is computed based on the weighted average number of common shares outstanding during the year. Diluted earnings per share is computed using the weighted average number of common shares outstanding and the effect of dilutive potential common shares outstanding during the year using the treasury stock method. Dilutive potential common shares consist of Restricted Stock Units and employee stock purchase plan shares. Unvested Performance Stock Units and related DERs are not included in the computation of dilutive securities because vesting of these instruments is dependent upon the attainment of required criteria over three-year performance periods. For additional information on Performance Stock Units and DERs, see Note 13, Stock-Based Compensation Expense.

Components of basic and diluted earnings per share are as follows:

	Years Ended December 31,
	2011		2010		2009
Numerator (in millions):
Net income attributable to Portland General Electric Company common shareholders	$	147	$	125	$	95
Denominator (in thousands):
Weighted average common shares outstanding—basic	75,333		75,275		72,790
Dilutive effect of unvested restricted stock units and employee stock purchase plan shares	17		16		62
Weighted average common shares outstanding—diluted	75,350		75,291		72,852
Earnings per share—basic and diluted	$	1.95	$	1.66	$	1.31

Basic and diluted earnings per share amounts are calculated based on actual amounts rather than the rounded amounts presented in the table above and on the consolidated statements of income. Accordingly, calculations using the rounded amounts presented for net income and weighted average shares outstanding may yield results that vary from the earnings per share amounts presented in the table above.