Stockholder's Equity | Stockholder’s Equity We have 5.4 million shares of common stock reserved for issuance under our Equity Incentive Plan (Plan) for our employees, officers, and directors. The Plan had 910,099 shares available for grant as of March 27, 2016 . (a) Stock Options The exercise price for stock options issued under the Plan is to be not less than the fair market value on the date of grant with respect to incentive and nonqualified stock options. Stock options vest in four equal annual installments and have a contractual life of seven years. Incentive stock options may be granted under this Plan until March 12, 2022. We issue new shares of common stock upon the exercise of stock options. Option activity is summarized for the three months ended March 27, 2016 as follows: Number of shares Weighted average exercise price Average remaining contractual life (years) Aggregate intrinsic value Outstanding, December 27, 2015 131,248 $ 113.12 4.0 $ 7,051 Exercised (6,392 ) 67.85 Cancelled (3,821 ) 152.93 Outstanding, March 27, 2016 121,035 $ 114.26 3.8 $ 4,788 Exercisable, March 27, 2016 81,276 95.60 3.2 4,311 The aggregate intrinsic value in the table above is before applicable income taxes, based on our closing stock price of $144.84 as of the last business day of the three -month period ended March 27, 2016 , which would have been received by the optionees had all options been exercised and sold on that date. As of March 27, 2016 , total unrecognized stock-based compensation expense related to nonvested stock options was approximately $1,600 , which is expected to be recognized over a weighted average period of approximately 2.2 years . During the three -month periods ended March 27, 2016 and March 29, 2015 , the total intrinsic value of stock options exercised was $533 and $288 , respectively. No shares were granted or vested during the three -month periods ended March 27, 2016 or March 29, 2015 . (b) Restricted Stock Units Restricted stock units are granted annually under the Plan at the discretion of the Compensation Committee of our Board of Directors. We grant restricted stock units subject to three -year cliff vesting and a cumulative three -year earnings target. The number of units that vest at the end of the three-year period is based on performance against the target. These restricted stock units are subject to forfeiture if they have not vested at the end of the three-year period. Stock-based compensation is recognized for the number of units expected to vest at the end of the period and is expensed beginning on the grant date through the end of the performance period. For each grant, restricted stock units meeting the performance criteria will vest as of the end of the third fiscal year in the performance period, subject to a Plan-specified maximum number of shares that may be issued to any individual in any year in settlement of restricted stock units. The distribution of vested restricted stock units as common stock typically occurs in March of the following year. The common stock is issued to participants net of the number of shares needed for the required minimum employee withholding taxes. We issue new shares of common stock upon the disbursement of restricted stock units. Restricted stock units are contingently issuable shares, and the activity for the three months ended March 27, 2016 was as follows: Number of shares Weighted average grant date fair value Outstanding, December 27, 2015 190,120 $ 161.06 Cancelled (6,772 ) 166.88 Outstanding, March 27, 2016 183,348 $ 160.85 As of March 27, 2016 , the total stock-based compensation expense related to nonvested awards not yet recognized was $7,181 , which is expected to be recognized over a weighted average period of 1.3 years. No shares were granted or vested during the three -month periods ended March 27, 2016 and March 29, 2015 . During the three -month periods ended March 27, 2016 and March 29, 2015 , we recognized $1,111 and $2,317 , respectively, of stock-based compensation expense related to restricted stock units. (c) Employee Stock Purchase Plan We have reserved 600,000 shares of common stock for issuance under our Employee Stock Purchase Plan (ESPP). The ESPP is available to substantially all employees subject to employment eligibility requirements. Participants may purchase our common stock at 85% of the beginning or ending closing price, whichever is lower, for each six-month period ending in May and November. During the three -month periods ended March 27, 2016 , and March 29, 2015 , we issued no shares of common stock under the ESPP. As of March 27, 2016 , we had 185,758 shares available for future issuance under the ESPP. |