UNS ENERGY EARNINGS PER SHARE - Shares of Common Stock Excluded from Computation of Diluted Earning Per Share (Detail)	3 Months Ended
Mar. 31, 2013
Anti-Dilutive Shares Excluded from the Diluted EPS Computation	24,000

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References+ Details