Basic and Diluted Earnings (Loss) Per Share

6 Months Ended

Jun. 30, 2011

Earnings Per Share [Abstract]

Basic and Diluted Earnings (Loss) Per Share

Basic and Diluted Earnings (Loss) Per Share

Basic earnings (loss) per share is computed by dividing net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income attributable to common stockholders by the sum of the weighted-average number of common shares outstanding during the period and the weighted-average number of dilutive common share equivalents outstanding during the period, using the treasury stock method and the if-converted method, where applicable. Dilutive common share equivalents are comprised of stock options, restricted stock awards, employee stock purchase rights and convertible senior notes. Since the Company incurred losses for the three and six months ended June 30, 2011 and 2010, 9.0 million and 9.7 million common share equivalents were excluded in the computation of diluted loss per share, for the three and six months ended June 30, 2011 and 2010, respectively.